com.unity.netcode.gameobjects@1.1.0

The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/) and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).

Additional documentation and release notes are available at [Multiplayer Documentation](https://docs-multiplayer.unity3d.com).

## [1.1.0] - 2022-10-21

### Added

- Added `NetworkManager.IsApproved` flag that is set to `true` a client has been approved.(#2261)
- `UnityTransport` now provides a way to set the Relay server data directly from the `RelayServerData` structure (provided by the Unity Transport package) throuh its `SetRelayServerData` method. This allows making use of the new APIs in UTP 1.3 that simplify integration of the Relay SDK. (#2235)
- IPv6 is now supported for direct connections when using `UnityTransport`. (#2232)
- Added WebSocket support when using UTP 2.0 with `UseWebSockets` property in the `UnityTransport` component of the `NetworkManager` allowing to pick WebSockets for communication. When building for WebGL, this selection happens automatically. (#2201)
- Added position, rotation, and scale to the `ParentSyncMessage` which provides users the ability to specify the final values on the server-side when `OnNetworkObjectParentChanged` is invoked just before the message is created (when the `Transform` values are applied to the message). (#2146)
- Added `NetworkObject.TryRemoveParent` method for convenience purposes opposed to having to cast null to either `GameObject` or `NetworkObject`. (#2146)

### Changed

- Updated `UnityTransport` dependency on `com.unity.transport` to 1.3.0. (#2231)
- The send queues of `UnityTransport` are now dynamically-sized. This means that there shouldn't be any need anymore to tweak the 'Max Send Queue Size' value. In fact, this field is now removed from the inspector and will not be serialized anymore. It is still possible to set it manually using the `MaxSendQueueSize` property, but it is not recommended to do so aside from some specific needs (e.g. limiting the amount of memory used by the send queues in very constrained environments). (#2212)
- As a consequence of the above change, the `UnityTransport.InitialMaxSendQueueSize` field is now deprecated. There is no default value anymore since send queues are dynamically-sized. (#2212)
- The debug simulator in `UnityTransport` is now non-deterministic. Its random number generator used to be seeded with a constant value, leading to the same pattern of packet drops, delays, and jitter in every run. (#2196)
- `NetworkVariable<>` now supports managed `INetworkSerializable` types, as well as other managed types with serialization/deserialization delegates registered to `UserNetworkVariableSerialization<T>.WriteValue` and `UserNetworkVariableSerialization<T>.ReadValue` (#2219)
- `NetworkVariable<>` and `BufferSerializer<BufferSerializerReader>` now deserialize `INetworkSerializable` types in-place, rather than constructing new ones. (#2219)

### Fixed

- Fixed `NetworkManager.ApprovalTimeout` will not timeout due to slower client synchronization times as it now uses the added `NetworkManager.IsApproved` flag to determined if the client has been approved or not.(#2261)
- Fixed issue caused when changing ownership of objects hidden to some clients (#2242)
- Fixed issue where an in-scene placed NetworkObject would not invoke NetworkBehaviour.OnNetworkSpawn if the GameObject was disabled when it was despawned. (#2239)
- Fixed issue where clients were not rebuilding the `NetworkConfig` hash value for each unique connection request. (#2226)
- Fixed the issue where player objects were not taking the `DontDestroyWithOwner` property into consideration when a client disconnected. (#2225)
- Fixed issue where `SceneEventProgress` would not complete if a client late joins while it is still in progress. (#2222)
- Fixed issue where `SceneEventProgress` would not complete if a client disconnects. (#2222)
- Fixed issues with detecting if a `SceneEventProgress` has timed out. (#2222)
- Fixed issue #1924 where `UnityTransport` would fail to restart after a first failure (even if what caused the initial failure was addressed). (#2220)
- Fixed issue where `NetworkTransform.SetStateServerRpc` and `NetworkTransform.SetStateClientRpc` were not honoring local vs world space settings when applying the position and rotation. (#2203)
- Fixed ILPP `TypeLoadException` on WebGL on MacOS Editor and potentially other platforms. (#2199)
- Implicit conversion of NetworkObjectReference to GameObject will now return null instead of throwing an exception if the referenced object could not be found (i.e., was already despawned) (#2158)
- Fixed warning resulting from a stray NetworkAnimator.meta file (#2153)
- Fixed Connection Approval Timeout not working client side. (#2164)
- Fixed issue where the `WorldPositionStays` parenting parameter was not being synchronized with clients. (#2146)
- Fixed issue where parented in-scene placed `NetworkObject`s would fail for late joining clients. (#2146)
- Fixed issue where scale was not being synchronized which caused issues with nested parenting and scale when `WorldPositionStays` was true. (#2146)
- Fixed issue with `NetworkTransform.ApplyTransformToNetworkStateWithInfo` where it was not honoring axis sync settings when `NetworkTransformState.IsTeleportingNextFrame` was true. (#2146)
- Fixed issue with `NetworkTransform.TryCommitTransformToServer` where it was not honoring the `InLocalSpace` setting. (#2146)
- Fixed ClientRpcs always reporting in the profiler view as going to all clients, even when limited to a subset of clients by `ClientRpcParams`. (#2144)
- Fixed RPC codegen failing to choose the correct extension methods for `FastBufferReader` and `FastBufferWriter` when the parameters were a generic type (i.e., List<int>) and extensions for multiple instantiations of that type have been defined (i.e., List<int> and List<string>) (#2142)
- Fixed the issue where running a server (i.e. not host) the second player would not receive updates (unless a third player joined). (#2127)
- Fixed issue where late-joining client transition synchronization could fail when more than one transition was occurring.(#2127)
- Fixed throwing an exception in `OnNetworkUpdate` causing other `OnNetworkUpdate` calls to not be executed. (#1739)
- Fixed synchronization when Time.timeScale is set to 0. This changes timing update to use unscaled deltatime. Now network updates rate are independent from the local time scale. (#2171)
- Fixed not sending all NetworkVariables to all clients when a client connects to a server. (#1987)
- Fixed IsOwner/IsOwnedByServer being wrong on the server after calling RemoveOwnership (#2211)

CHANGELOG.md

@@ -1,3 +1,4 @@
+
 # Changelog
 
 All notable changes to this project will be documented in this file.
@@ -6,6 +7,93 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/)
 
 Additional documentation and release notes are available at [Multiplayer Documentation](https://docs-multiplayer.unity3d.com).
 
+## [1.1.0] - 2022-10-21
+
+### Added
+
+- Added `NetworkManager.IsApproved` flag that is set to `true` a client has been approved.(#2261)
+- `UnityTransport` now provides a way to set the Relay server data directly from the `RelayServerData` structure (provided by the Unity Transport package) throuh its `SetRelayServerData` method. This allows making use of the new APIs in UTP 1.3 that simplify integration of the Relay SDK. (#2235)
+- IPv6 is now supported for direct connections when using `UnityTransport`. (#2232)
+- Added WebSocket support when using UTP 2.0 with `UseWebSockets` property in the `UnityTransport` component of the `NetworkManager` allowing to pick WebSockets for communication. When building for WebGL, this selection happens automatically. (#2201)
+- Added position, rotation, and scale to the `ParentSyncMessage` which provides users the ability to specify the final values on the server-side when `OnNetworkObjectParentChanged` is invoked just before the message is created (when the `Transform` values are applied to the message). (#2146)
+- Added `NetworkObject.TryRemoveParent` method for convenience purposes opposed to having to cast null to either `GameObject` or `NetworkObject`. (#2146)
+
+### Changed
+
+- Updated `UnityTransport` dependency on `com.unity.transport` to 1.3.0. (#2231)
+- The send queues of `UnityTransport` are now dynamically-sized. This means that there shouldn't be any need anymore to tweak the 'Max Send Queue Size' value. In fact, this field is now removed from the inspector and will not be serialized anymore. It is still possible to set it manually using the `MaxSendQueueSize` property, but it is not recommended to do so aside from some specific needs (e.g. limiting the amount of memory used by the send queues in very constrained environments). (#2212)
+- As a consequence of the above change, the `UnityTransport.InitialMaxSendQueueSize` field is now deprecated. There is no default value anymore since send queues are dynamically-sized. (#2212)
+- The debug simulator in `UnityTransport` is now non-deterministic. Its random number generator used to be seeded with a constant value, leading to the same pattern of packet drops, delays, and jitter in every run. (#2196)
+- `NetworkVariable<>` now supports managed `INetworkSerializable` types, as well as other managed types with serialization/deserialization delegates registered to `UserNetworkVariableSerialization<T>.WriteValue` and `UserNetworkVariableSerialization<T>.ReadValue` (#2219)
+- `NetworkVariable<>` and `BufferSerializer<BufferSerializerReader>` now deserialize `INetworkSerializable` types in-place, rather than constructing new ones. (#2219)
+
+### Fixed
+
+- Fixed `NetworkManager.ApprovalTimeout` will not timeout due to slower client synchronization times as it now uses the added `NetworkManager.IsApproved` flag to determined if the client has been approved or not.(#2261)
+- Fixed issue caused when changing ownership of objects hidden to some clients (#2242)
+- Fixed issue where an in-scene placed NetworkObject would not invoke NetworkBehaviour.OnNetworkSpawn if the GameObject was disabled when it was despawned. (#2239)
+- Fixed issue where clients were not rebuilding the `NetworkConfig` hash value for each unique connection request. (#2226)
+- Fixed the issue where player objects were not taking the `DontDestroyWithOwner` property into consideration when a client disconnected. (#2225)
+- Fixed issue where `SceneEventProgress` would not complete if a client late joins while it is still in progress. (#2222)
+- Fixed issue where `SceneEventProgress` would not complete if a client disconnects. (#2222)
+- Fixed issues with detecting if a `SceneEventProgress` has timed out. (#2222)
+- Fixed issue #1924 where `UnityTransport` would fail to restart after a first failure (even if what caused the initial failure was addressed). (#2220)
+- Fixed issue where `NetworkTransform.SetStateServerRpc` and `NetworkTransform.SetStateClientRpc` were not honoring local vs world space settings when applying the position and rotation. (#2203)
+- Fixed ILPP `TypeLoadException` on WebGL on MacOS Editor and potentially other platforms. (#2199)
+- Implicit conversion of NetworkObjectReference to GameObject will now return null instead of throwing an exception if the referenced object could not be found (i.e., was already despawned) (#2158)
+- Fixed warning resulting from a stray NetworkAnimator.meta file (#2153)
+- Fixed Connection Approval Timeout not working client side. (#2164)
+- Fixed issue where the `WorldPositionStays` parenting parameter was not being synchronized with clients. (#2146)
+- Fixed issue where parented in-scene placed `NetworkObject`s would fail for late joining clients. (#2146)
+- Fixed issue where scale was not being synchronized which caused issues with nested parenting and scale when `WorldPositionStays` was true. (#2146)
+- Fixed issue with `NetworkTransform.ApplyTransformToNetworkStateWithInfo` where it was not honoring axis sync settings when `NetworkTransformState.IsTeleportingNextFrame` was true. (#2146)
+- Fixed issue with `NetworkTransform.TryCommitTransformToServer` where it was not honoring the `InLocalSpace` setting. (#2146)
+- Fixed ClientRpcs always reporting in the profiler view as going to all clients, even when limited to a subset of clients by `ClientRpcParams`. (#2144)
+- Fixed RPC codegen failing to choose the correct extension methods for `FastBufferReader` and `FastBufferWriter` when the parameters were a generic type (i.e., List<int>) and extensions for multiple instantiations of that type have been defined (i.e., List<int> and List<string>) (#2142)
+- Fixed the issue where running a server (i.e. not host) the second player would not receive updates (unless a third player joined). (#2127)
+- Fixed issue where late-joining client transition synchronization could fail when more than one transition was occurring.(#2127)
+- Fixed throwing an exception in `OnNetworkUpdate` causing other `OnNetworkUpdate` calls to not be executed. (#1739)
+- Fixed synchronization when Time.timeScale is set to 0. This changes timing update to use unscaled deltatime. Now network updates rate are independent from the local time scale. (#2171)
+- Fixed not sending all NetworkVariables to all clients when a client connects to a server. (#1987)
+- Fixed IsOwner/IsOwnedByServer being wrong on the server after calling RemoveOwnership (#2211)
+
+## [1.0.2] - 2022-09-12
+
+### Fixed
+
+- Fixed issue where `NetworkTransform` was not honoring the InLocalSpace property on the authority side during OnNetworkSpawn. (#2170)
+- Fixed issue where `NetworkTransform` was not ending extrapolation for the previous state causing non-authoritative instances to become out of synch. (#2170)
+- Fixed issue where `NetworkTransform` was not continuing to interpolate for the remainder of the associated tick period. (#2170)
+- Fixed issue during `NetworkTransform.OnNetworkSpawn` for non-authoritative instances where it was initializing interpolators with the replicated network state which now only contains the transform deltas that occurred during a network tick and not the entire transform state. (#2170)
+
+## [1.0.1] - 2022-08-23
+
+### Changed
+
+- Changed version to 1.0.1. (#2131)
+- Updated dependency on `com.unity.transport` to 1.2.0. (#2129)
+- When using `UnityTransport`, _reliable_ payloads are now allowed to exceed the configured 'Max Payload Size'. Unreliable payloads remain bounded by this setting. (#2081)
+- Performance improvements for cases with large number of NetworkObjects, by not iterating over all unchanged NetworkObjects
+
+### Fixed
+
+- Fixed an issue where reading/writing more than 8 bits at a time with BitReader/BitWriter would write/read from the wrong place, returning and incorrect result. (#2130)
+- Fixed issue with the internal `NetworkTransformState.m_Bitset` flag not getting cleared upon the next tick advancement. (#2110)
+- Fixed interpolation issue with `NetworkTransform.Teleport`. (#2110)
+- Fixed issue where the authoritative side was interpolating its transform. (#2110)
+- Fixed Owner-written NetworkVariable infinitely write themselves (#2109)
+- Fixed NetworkList issue that showed when inserting at the very end of a NetworkList (#2099)
+- Fixed issue where a client owner of a `NetworkVariable` with both owner read and write permissions would not update the server side when changed. (#2097)
+- Fixed issue when attempting to spawn a parent `GameObject`, with `NetworkObject` component attached, that has one or more child `GameObject`s, that are inactive in the hierarchy, with `NetworkBehaviour` components it will no longer attempt to spawn the associated `NetworkBehaviour`(s) or invoke ownership changed notifications but will log a warning message. (#2096)
+- Fixed an issue where destroying a NetworkBehaviour would not deregister it from the parent NetworkObject, leading to exceptions when the parent was later destroyed. (#2091)
+- Fixed issue where `NetworkObject.NetworkHide` was despawning and destroying, as opposed to only despawning, in-scene placed `NetworkObject`s. (#2086)
+- Fixed `NetworkAnimator` synchronizing transitions twice due to it detecting the change in animation state once a transition is started by a trigger. (#2084)
+- Fixed issue where `NetworkAnimator` would not synchronize a looping animation for late joining clients if it was at the very end of its loop. (#2076)
+- Fixed issue where `NetworkAnimator` was not removing its subscription from `OnClientConnectedCallback` when despawned during the shutdown sequence. (#2074)
+- Fixed IsServer and IsClient being set to false before object despawn during the shutdown sequence. (#2074)
+- Fixed NetworkList Value event on the server. PreviousValue is now set correctly when a new value is set through property setter. (#2067)
+- Fixed NetworkLists not populating on client. NetworkList now uses the most recent list as opposed to the list at the end of previous frame, when sending full updates to dynamically spawned NetworkObject. The difference in behaviour is required as scene management spawns those objects at a different time in the frame, relative to updates. (#2062)
+
 ## [1.0.0] - 2022-06-27
 
 ### Changed
@@ -202,7 +290,7 @@ Additional documentation and release notes are available at [Multiplayer Documen
 
 - ResetTrigger function to NetworkAnimator (#1327)
 
-### Fixed 
+### Fixed
 
 - Overflow exception when syncing Animator state. (#1327)
 - Added `try`/`catch` around RPC calls, preventing exception from causing further RPC calls to fail (#1329)
@@ -227,7 +315,7 @@ Additional documentation and release notes are available at [Multiplayer Documen
 - Added `ClientNetworkTransform` sample to the SDK package (#1168)
 - Added `Bootstrap` sample to the SDK package (#1140)
 - Enhanced `NetworkSceneManager` implementation with additive scene loading capabilities (#1080, #955, #913)
-  - `NetworkSceneManager.OnSceneEvent` provides improved scene event notificaitons  
+  - `NetworkSceneManager.OnSceneEvent` provides improved scene event notificaitons
 - Enhanced `NetworkTransform` implementation with per axis/component based and threshold based state replication (#1042, #1055, #1061, #1084, #1101)
 - Added a jitter-resistent `BufferedLinearInterpolator<T>` for `NetworkTransform` (#1060)
 - Implemented `NetworkPrefabHandler` that provides support for object pooling and `NetworkPrefab` overrides (#1073, #1004, #977, #905,#749, #727)
@@ -284,7 +372,7 @@ Additional documentation and release notes are available at [Multiplayer Documen
 - Removed `NetworkDictionary`, `NetworkSet` (#1149)
 - Removed `NetworkVariableSettings` (#1097)
 - Removed predefined `NetworkVariable<T>` types (#1093)
-    - Removed `NetworkVariableBool`, `NetworkVariableByte`, `NetworkVariableSByte`, `NetworkVariableUShort`, `NetworkVariableShort`, `NetworkVariableUInt`, `NetworkVariableInt`, `NetworkVariableULong`, `NetworkVariableLong`, `NetworkVariableFloat`, `NetworkVariableDouble`, `NetworkVariableVector2`, `NetworkVariableVector3`, `NetworkVariableVector4`, `NetworkVariableColor`, `NetworkVariableColor32`, `NetworkVariableRay`, `NetworkVariableQuaternion`
+  - Removed `NetworkVariableBool`, `NetworkVariableByte`, `NetworkVariableSByte`, `NetworkVariableUShort`, `NetworkVariableShort`, `NetworkVariableUInt`, `NetworkVariableInt`, `NetworkVariableULong`, `NetworkVariableLong`, `NetworkVariableFloat`, `NetworkVariableDouble`, `NetworkVariableVector2`, `NetworkVariableVector3`, `NetworkVariableVector4`, `NetworkVariableColor`, `NetworkVariableColor32`, `NetworkVariableRay`, `NetworkVariableQuaternion`
 - Removed `NetworkChannel` and `MultiplexTransportAdapter` (#1133)
 - Removed ILPP backend for 2019.4, minimum required version is 2020.3+ (#895)
 - `NetworkManager.NetworkConfig` had the following properties removed: (#1080)
@@ -356,14 +444,14 @@ This is the initial experimental Unity MLAPI Package, v0.1.0.
 - Integrated MLAPI with the Unity Profiler for versions 2020.2 and later:
   - Added new profiler modules for MLAPI that report important network data.
   - Attached the profiler to a remote player to view network data over the wire.
-- A test project is available for building and experimenting with MLAPI features. This project is available in the MLAPI GitHub [testproject folder](https://github.com/Unity-Technologies/com.unity.multiplayer.mlapi/tree/release/0.1.0/testproject). 
+- A test project is available for building and experimenting with MLAPI features. This project is available in the MLAPI GitHub [testproject folder](https://github.com/Unity-Technologies/com.unity.multiplayer.mlapi/tree/release/0.1.0/testproject).
 - Added a [MLAPI Community Contributions](https://github.com/Unity-Technologies/mlapi-community-contributions/tree/master/com.mlapi.contrib.extensions) new GitHub repository to accept extensions from the MLAPI community. Current extensions include moved MLAPI features for lag compensation (useful for Server Authoritative actions) and `TrackedObject`.
 
 ### Changed
 
 - [GitHub 520](https://github.com/Unity-Technologies/com.unity.multiplayer.mlapi/pull/520): MLAPI now uses the Unity Package Manager for installation management.
-- Added functionality and usability to `NetworkVariable`, previously called `NetworkVar`. Updates enhance options and fully replace the need for `SyncedVar`s. 
-- [GitHub 507](https://github.com/Unity-Technologies/com.unity.multiplayer.mlapi/pull/507): Reimplemented `NetworkAnimator`, which synchronizes animation states for networked objects. 
+- Added functionality and usability to `NetworkVariable`, previously called `NetworkVar`. Updates enhance options and fully replace the need for `SyncedVar`s.
+- [GitHub 507](https://github.com/Unity-Technologies/com.unity.multiplayer.mlapi/pull/507): Reimplemented `NetworkAnimator`, which synchronizes animation states for networked objects.
 - GitHub [444](https://github.com/Unity-Technologies/com.unity.multiplayer.mlapi/pull/444) and [455](https://github.com/Unity-Technologies/com.unity.multiplayer.mlapi/pull/455): Channels are now represented as bytes instead of strings.
 
 For users of previous versions of MLAPI, this release renames APIs due to refactoring. All obsolete marked APIs have been removed as per [GitHub 513](https://github.com/Unity-Technologies/com.unity.multiplayer.mlapi/pull/513) and [GitHub 514](https://github.com/Unity-Technologies/com.unity.multiplayer.mlapi/pull/514).
@@ -396,7 +484,7 @@ For users of previous versions of MLAPI, this release renames APIs due to refact
 
 ### Fixed
 
-- [GitHub 460](https://github.com/Unity-Technologies/com.unity.multiplayer.mlapi/pull/460): Fixed an issue for RPC where the host-server was not receiving RPCs from the host-client and vice versa without the loopback flag set in `NetworkingManager`. 
+- [GitHub 460](https://github.com/Unity-Technologies/com.unity.multiplayer.mlapi/pull/460): Fixed an issue for RPC where the host-server was not receiving RPCs from the host-client and vice versa without the loopback flag set in `NetworkingManager`.
 - Fixed an issue where data in the Profiler was incorrectly aggregated and drawn, which caused the profiler data to increment indefinitely instead of resetting each frame.
 - Fixed an issue the client soft-synced causing PlayMode client-only scene transition issues, caused when running the client in the editor and the host as a release build. Users may have encountered a soft sync of `NetworkedInstanceId` issues in the `SpawnManager.ClientCollectSoftSyncSceneObjectSweep` method.
 - [GitHub 458](https://github.com/Unity-Technologies/com.unity.multiplayer.mlapi/pull/458): Fixed serialization issues in `NetworkList` and `NetworkDictionary` when running in Server mode.
@@ -411,10 +499,10 @@ With a new release of MLAPI in Unity, some features have been removed:
 - SyncVars have been removed from MLAPI. Use `NetworkVariable`s in place of this functionality. <!-- MTT54 -->
 - [GitHub 527](https://github.com/Unity-Technologies/com.unity.multiplayer.mlapi/pull/527): Lag compensation systems and `TrackedObject` have moved to the new [MLAPI Community Contributions](https://github.com/Unity-Technologies/mlapi-community-contributions/tree/master/com.mlapi.contrib.extensions) repo.
 - [GitHub 509](https://github.com/Unity-Technologies/com.unity.multiplayer.mlapi/pull/509): Encryption has been removed from MLAPI. The `Encryption` option in `NetworkConfig` on the `NetworkingManager` is not available in this release. This change will not block game creation or running. A current replacement for this functionality is not available, and may be developed in future releases. See the following changes:
-    - Removed `SecuritySendFlags` from all APIs.
-    - Removed encryption, cryptography, and certificate configurations from APIs including `NetworkManager` and `NetworkConfig`.
-    - Removed "hail handshake", including `NetworkManager` implementation and `NetworkConstants` entries.
-    - Modified `RpcQueue` and `RpcBatcher` internals to remove encryption and authentication from reading and writing.
+  - Removed `SecuritySendFlags` from all APIs.
+  - Removed encryption, cryptography, and certificate configurations from APIs including `NetworkManager` and `NetworkConfig`.
+  - Removed "hail handshake", including `NetworkManager` implementation and `NetworkConstants` entries.
+  - Modified `RpcQueue` and `RpcBatcher` internals to remove encryption and authentication from reading and writing.
 - Removed the previous MLAPI Profiler editor window from Unity versions 2020.2 and later.
 - Removed previous MLAPI Convenience and Performance RPC APIs with the new standard RPC API. See [RFC #1](https://github.com/Unity-Technologies/com.unity.multiplayer.rfcs/blob/master/text/0001-std-rpc-api.md) for details.
 - [GitHub 520](https://github.com/Unity-Technologies/com.unity.multiplayer.mlapi/pull/520): Removed the MLAPI Installer.
@@ -427,7 +515,7 @@ With a new release of MLAPI in Unity, some features have been removed:
 - For `NetworkVariable`, the `NetworkDictionary` `List` and `Set` must use the `reliableSequenced` channel.
 - `NetworkObjects`s are supported but when spawning a prefab with nested child network objects you have to manually call spawn on them
 - `NetworkTransform` have the following issues:
-  - Replicated objects may have jitter. 
+  - Replicated objects may have jitter.
   - The owner is always authoritative about the object's position.
   - Scale is not synchronized.
 - Connection Approval is not called on the host client.

Components/Interpolator/BufferedLinearInterpolator.cs

@@ -248,6 +248,8 @@ namespace Unity.Netcode
                 return;
             }
 
+            // Part the of reason for disabling extrapolation is how we add and use measurements over time.
+            // TODO: Add detailed description of this area in Jira ticket
             if (sentTime > m_EndTimeConsumed || m_LifetimeConsumedCount == 0) // treat only if value is newer than the one being interpolated to right now
             {
                 m_LastBufferedItemReceived = new BufferedItem(newMeasurement, sentTime);
@@ -292,7 +294,9 @@ namespace Unity.Netcode
         /// <inheritdoc />
         protected override float InterpolateUnclamped(float start, float end, float time)
         {
-            return Mathf.LerpUnclamped(start, end, time);
+            // Disabling Extrapolation:
+            // TODO: Add Jira Ticket
+            return Mathf.Lerp(start, end, time);
         }
 
         /// <inheritdoc />
@@ -311,13 +315,17 @@ namespace Unity.Netcode
         /// <inheritdoc />
         protected override Quaternion InterpolateUnclamped(Quaternion start, Quaternion end, float time)
         {
-            return Quaternion.SlerpUnclamped(start, end, time);
+            // Disabling Extrapolation:
+            // TODO: Add Jira Ticket
+            return Quaternion.Slerp(start, end, time);
         }
 
         /// <inheritdoc />
         protected override Quaternion Interpolate(Quaternion start, Quaternion end, float time)
         {
-            return Quaternion.SlerpUnclamped(start, end, time);
+            // Disabling Extrapolation:
+            // TODO: Add Jira Ticket
+            return Quaternion.Slerp(start, end, time);
         }
     }
 }

Components/NetworkAnimator.cs

@@ -1,14 +1,19 @@
 #if COM_UNITY_MODULES_ANIMATION
+using System;
 using System.Collections.Generic;
 using Unity.Collections;
 using Unity.Collections.LowLevel.Unsafe;
 using UnityEngine;
+#if UNITY_EDITOR
+using UnityEditor.Animations;
+#endif
 
 namespace Unity.Netcode.Components
 {
     internal class NetworkAnimatorStateChangeHandler : INetworkUpdateSystem
     {
         private NetworkAnimator m_NetworkAnimator;
+        private bool m_IsServer;
 
         /// <summary>
         /// This removes sending RPCs from within RPCs when the
@@ -32,7 +37,14 @@ namespace Unity.Netcode.Components
 
             foreach (var sendEntry in m_SendTriggerUpdates)
             {
-                m_NetworkAnimator.SendAnimTriggerClientRpc(sendEntry.AnimationTriggerMessage, sendEntry.ClientRpcParams);
+                if (!sendEntry.SendToServer)
+                {
+                    m_NetworkAnimator.SendAnimTriggerClientRpc(sendEntry.AnimationTriggerMessage, sendEntry.ClientRpcParams);
+                }
+                else
+                {
+                    m_NetworkAnimator.SendAnimTriggerServerRpc(sendEntry.AnimationTriggerMessage);
+                }
             }
             m_SendTriggerUpdates.Clear();
         }
@@ -44,8 +56,8 @@ namespace Unity.Netcode.Components
             {
                 case NetworkUpdateStage.PreUpdate:
                     {
-                        // Only the server forwards messages and synchronizes players
-                        if (m_NetworkAnimator.NetworkManager.IsServer)
+                        // Only the owner or the server send messages
+                        if (m_NetworkAnimator.IsOwner || m_IsServer)
                         {
                             // Flush any pending messages
                             FlushMessages();
@@ -125,6 +137,7 @@ namespace Unity.Netcode.Components
 
         private struct TriggerUpdate
         {
+            public bool SendToServer;
             public ClientRpcParams ClientRpcParams;
             public NetworkAnimator.AnimationTriggerMessage AnimationTriggerMessage;
         }
@@ -134,11 +147,23 @@ namespace Unity.Netcode.Components
         /// <summary>
         /// Invoked when a server needs to forward an update to a Trigger state
         /// </summary>
-        internal void SendTriggerUpdate(NetworkAnimator.AnimationTriggerMessage animationTriggerMessage, ClientRpcParams clientRpcParams = default)
+        internal void QueueTriggerUpdateToClient(NetworkAnimator.AnimationTriggerMessage animationTriggerMessage, ClientRpcParams clientRpcParams = default)
         {
             m_SendTriggerUpdates.Add(new TriggerUpdate() { ClientRpcParams = clientRpcParams, AnimationTriggerMessage = animationTriggerMessage });
         }
 
+        internal void QueueTriggerUpdateToServer(NetworkAnimator.AnimationTriggerMessage animationTriggerMessage)
+        {
+            m_SendTriggerUpdates.Add(new TriggerUpdate() { AnimationTriggerMessage = animationTriggerMessage, SendToServer = true });
+        }
+
+        private Queue<NetworkAnimator.AnimationMessage> m_AnimationMessageQueue = new Queue<NetworkAnimator.AnimationMessage>();
+
+        internal void AddAnimationMessageToProcessQueue(NetworkAnimator.AnimationMessage message)
+        {
+            m_AnimationMessageQueue.Enqueue(message);
+        }
+
         internal void DeregisterUpdate()
         {
             NetworkUpdateLoop.UnregisterNetworkUpdate(this, NetworkUpdateStage.PreUpdate);
@@ -147,33 +172,266 @@ namespace Unity.Netcode.Components
         internal NetworkAnimatorStateChangeHandler(NetworkAnimator networkAnimator)
         {
             m_NetworkAnimator = networkAnimator;
+            m_IsServer = networkAnimator.NetworkManager.IsServer;
             NetworkUpdateLoop.RegisterNetworkUpdate(this, NetworkUpdateStage.PreUpdate);
         }
     }
 
-
-
     /// <summary>
     /// NetworkAnimator enables remote synchronization of <see cref="UnityEngine.Animator"/> state for on network objects.
     /// </summary>
-    [AddComponentMenu("Netcode/" + nameof(NetworkAnimator))]
+    [AddComponentMenu("Netcode/Network Animator")]
     [RequireComponent(typeof(Animator))]
-    public class NetworkAnimator : NetworkBehaviour
+    public class NetworkAnimator : NetworkBehaviour, ISerializationCallbackReceiver
+
     {
-        internal struct AnimationMessage : INetworkSerializable
+        [Serializable]
+        internal class TransitionStateinfo
         {
-            // state hash per layer.  if non-zero, then Play() this animation, skipping transitions
+            public int Layer;
+            public int OriginatingState;
+            public int DestinationState;
+            public float TransitionDuration;
+            public int TriggerNameHash;
+            public int TransitionIndex;
+        }
+
+        /// <summary>
+        /// Used to build the destination state to transition info table
+        /// </summary>
+        [HideInInspector]
+        [SerializeField]
+        internal List<TransitionStateinfo> TransitionStateInfoList;
+
+        // Used to get the associated transition information required to synchronize late joining clients with transitions
+        // [Layer][DestinationState][TransitionStateInfo]
+        private Dictionary<int, Dictionary<int, TransitionStateinfo>> m_DestinationStateToTransitioninfo = new Dictionary<int, Dictionary<int, TransitionStateinfo>>();
+
+        /// <summary>
+        /// Builds the m_DestinationStateToTransitioninfo lookup table
+        /// </summary>
+        private void BuildDestinationToTransitionInfoTable()
+        {
+            foreach (var entry in TransitionStateInfoList)
+            {
+                if (!m_DestinationStateToTransitioninfo.ContainsKey(entry.Layer))
+                {
+                    m_DestinationStateToTransitioninfo.Add(entry.Layer, new Dictionary<int, TransitionStateinfo>());
+                }
+                var destinationStateTransitionInfo = m_DestinationStateToTransitioninfo[entry.Layer];
+                if (!destinationStateTransitionInfo.ContainsKey(entry.DestinationState))
+                {
+                    destinationStateTransitionInfo.Add(entry.DestinationState, entry);
+                }
+            }
+        }
+
+        /// <summary>
+        /// Creates the TransitionStateInfoList table
+        /// </summary>
+        private void BuildTransitionStateInfoList()
+        {
+#if UNITY_EDITOR
+            if (UnityEditor.EditorApplication.isUpdating)
+            {
+                return;
+            }
+            TransitionStateInfoList = new List<TransitionStateinfo>();
+            var animatorController = m_Animator.runtimeAnimatorController as AnimatorController;
+            if (animatorController == null)
+            {
+                return;
+            }
+
+            for (int x = 0; x < animatorController.layers.Length; x++)
+            {
+                var layer = animatorController.layers[x];
+
+                for (int y = 0; y < layer.stateMachine.states.Length; y++)
+                {
+                    var animatorState = layer.stateMachine.states[y].state;
+                    var transitions = layer.stateMachine.GetStateMachineTransitions(layer.stateMachine);
+                    for (int z = 0; z < animatorState.transitions.Length; z++)
+                    {
+                        var transition = animatorState.transitions[z];
+                        if (transition.conditions.Length == 0 && transition.isExit)
+                        {
+                            // We don't need to worry about exit transitions with no conditions
+                            continue;
+                        }
+
+                        foreach (var condition in transition.conditions)
+                        {
+                            var parameterName = condition.parameter;
+                            var parameters = animatorController.parameters;
+                            foreach (var parameter in parameters)
+                            {
+                                switch (parameter.type)
+                                {
+                                    case AnimatorControllerParameterType.Trigger:
+                                        {
+                                            // Match the condition with an existing trigger
+                                            if (parameterName == parameter.name)
+                                            {
+                                                var transitionInfo = new TransitionStateinfo()
+                                                {
+                                                    Layer = x,
+                                                    OriginatingState = animatorState.nameHash,
+                                                    DestinationState = transition.destinationState.nameHash,
+                                                    TransitionDuration = transition.duration,
+                                                    TriggerNameHash = parameter.nameHash,
+                                                    TransitionIndex = z
+                                                };
+                                                TransitionStateInfoList.Add(transitionInfo);
+                                            }
+                                            break;
+                                        }
+                                    default:
+                                        break;
+                                }
+                            }
+                        }
+                    }
+                }
+            }
+#endif
+        }
+
+        public void OnAfterDeserialize()
+        {
+            BuildDestinationToTransitionInfoTable();
+        }
+
+        public void OnBeforeSerialize()
+        {
+            BuildTransitionStateInfoList();
+        }
+
+        internal struct AnimationState : INetworkSerializable
+        {
+            // Not to be serialized, used for processing the animation state
+            internal bool HasBeenProcessed;
             internal int StateHash;
             internal float NormalizedTime;
             internal int Layer;
             internal float Weight;
 
+            // For synchronizing transitions
+            internal bool Transition;
+            // The StateHash is where the transition starts
+            // and the DestinationStateHash is the destination state
+            internal int DestinationStateHash;
+
             public void NetworkSerialize<T>(BufferSerializer<T> serializer) where T : IReaderWriter
             {
-                serializer.SerializeValue(ref StateHash);
-                serializer.SerializeValue(ref NormalizedTime);
-                serializer.SerializeValue(ref Layer);
-                serializer.SerializeValue(ref Weight);
+                if (serializer.IsWriter)
+                {
+                    var writer = serializer.GetFastBufferWriter();
+                    var writeSize = FastBufferWriter.GetWriteSize(Transition);
+                    writeSize += FastBufferWriter.GetWriteSize(StateHash);
+                    writeSize += FastBufferWriter.GetWriteSize(NormalizedTime);
+                    writeSize += FastBufferWriter.GetWriteSize(Layer);
+                    writeSize += FastBufferWriter.GetWriteSize(Weight);
+                    if (Transition)
+                    {
+                        writeSize += FastBufferWriter.GetWriteSize(DestinationStateHash);
+                    }
+
+                    if (!writer.TryBeginWrite(writeSize))
+                    {
+                        throw new OverflowException($"[{GetType().Name}] Could not serialize: Out of buffer space.");
+                    }
+
+                    writer.WriteValue(Transition);
+                    writer.WriteValue(StateHash);
+                    writer.WriteValue(NormalizedTime);
+                    writer.WriteValue(Layer);
+                    writer.WriteValue(Weight);
+                    if (Transition)
+                    {
+                        writer.WriteValue(DestinationStateHash);
+                    }
+                }
+                else
+                {
+                    var reader = serializer.GetFastBufferReader();
+                    // Begin reading the Transition flag
+                    if (!reader.TryBeginRead(FastBufferWriter.GetWriteSize(Transition)))
+                    {
+                        throw new OverflowException($"[{GetType().Name}] Could not deserialize: Out of buffer space.");
+                    }
+                    reader.ReadValue(out Transition);
+
+                    // Now determine what remains to be read
+                    var readSize = FastBufferWriter.GetWriteSize(StateHash);
+                    readSize += FastBufferWriter.GetWriteSize(NormalizedTime);
+                    readSize += FastBufferWriter.GetWriteSize(Layer);
+                    readSize += FastBufferWriter.GetWriteSize(Weight);
+                    if (Transition)
+                    {
+                        readSize += FastBufferWriter.GetWriteSize(DestinationStateHash);
+                    }
+
+                    // Now read the remaining information about this AnimationState
+                    if (!reader.TryBeginRead(readSize))
+                    {
+                        throw new OverflowException($"[{GetType().Name}] Could not deserialize: Out of buffer space.");
+                    }
+
+                    reader.ReadValue(out StateHash);
+                    reader.ReadValue(out NormalizedTime);
+                    reader.ReadValue(out Layer);
+                    reader.ReadValue(out Weight);
+                    if (Transition)
+                    {
+                        reader.ReadValue(out DestinationStateHash);
+                    }
+                }
+            }
+        }
+
+        internal struct AnimationMessage : INetworkSerializable
+        {
+            // Not to be serialized, used for processing the animation message
+            internal bool HasBeenProcessed;
+
+            // This is preallocated/populated in OnNetworkSpawn for all instances in the event ownership or
+            // authority changes.  When serializing, IsDirtyCount determines how many AnimationState entries
+            // should be serialized from the list.  When deserializing the list is created and populated with
+            // only the number of AnimationStates received which is dictated by the deserialized IsDirtyCount.
+            internal List<AnimationState> AnimationStates;
+
+            // Used to determine how many AnimationState entries we are sending or receiving
+            internal int IsDirtyCount;
+
+            public void NetworkSerialize<T>(BufferSerializer<T> serializer) where T : IReaderWriter
+            {
+                var animationState = new AnimationState();
+                if (serializer.IsReader)
+                {
+                    AnimationStates = new List<AnimationState>();
+
+                    serializer.SerializeValue(ref IsDirtyCount);
+                    // Since we create a new AnimationMessage when deserializing
+                    // we need to create new animation states for each incoming
+                    // AnimationState being updated
+                    for (int i = 0; i < IsDirtyCount; i++)
+                    {
+                        animationState = new AnimationState();
+                        serializer.SerializeValue(ref animationState);
+                        AnimationStates.Add(animationState);
+                    }
+                }
+                else
+                {
+                    // When writing, only send the counted dirty animation states
+                    serializer.SerializeValue(ref IsDirtyCount);
+                    for (int i = 0; i < IsDirtyCount; i++)
+                    {
+                        animationState = AnimationStates[i];
+                        serializer.SerializeNetworkSerializable(ref animationState);
+                    }
+                }
             }
         }
 
@@ -222,7 +480,8 @@ namespace Unity.Netcode.Components
             return true;
         }
 
-        // Animators only support up to 32 params
+        // Animators only support up to 32 parameters
+        // TODO: Look into making this a range limited property
         private const int k_MaxAnimationParams = 32;
 
         private int[] m_TransitionHash;
@@ -268,9 +527,9 @@ namespace Unity.Netcode.Components
                 m_NetworkAnimatorStateChangeHandler = null;
             }
 
-            if (IsServer)
+            if (m_CachedNetworkManager != null)
             {
-                NetworkManager.OnClientConnectedCallback -= OnClientConnectedCallback;
+                m_CachedNetworkManager.OnClientConnectedCallback -= OnClientConnectedCallback;
             }
 
             if (m_CachedAnimatorParameters != null && m_CachedAnimatorParameters.IsCreated)
@@ -292,40 +551,64 @@ namespace Unity.Netcode.Components
         private List<int> m_ParametersToUpdate;
         private List<ulong> m_ClientSendList;
         private ClientRpcParams m_ClientRpcParams;
+        private AnimationMessage m_AnimationMessage;
 
+        /// <summary>
+        /// Used for integration test to validate that the
+        /// AnimationMessage.AnimationStates remains the same
+        /// size as the layer count.
+        /// </summary>
+        internal AnimationMessage GetAnimationMessage()
+        {
+            return m_AnimationMessage;
+        }
+
+        // Only used in Cleanup
+        private NetworkManager m_CachedNetworkManager;
+
+        /// <inheritdoc/>
         public override void OnNetworkSpawn()
         {
-            if (IsOwner || IsServer)
+            int layers = m_Animator.layerCount;
+
+            // Initializing the below arrays for everyone handles an issue
+            // when running in owner authoritative mode and the owner changes.
+            m_TransitionHash = new int[layers];
+            m_AnimationHash = new int[layers];
+            m_LayerWeights = new float[layers];
+
+            if (IsServer)
             {
-                int layers = m_Animator.layerCount;
-                m_TransitionHash = new int[layers];
-                m_AnimationHash = new int[layers];
-                m_LayerWeights = new float[layers];
+                m_ClientSendList = new List<ulong>(128);
+                m_ClientRpcParams = new ClientRpcParams();
+                m_ClientRpcParams.Send = new ClientRpcSendParams();
+                m_ClientRpcParams.Send.TargetClientIds = m_ClientSendList;
 
-                if (IsServer)
-                {
-                    NetworkManager.OnClientConnectedCallback += OnClientConnectedCallback;
-                }
+                // Cache the NetworkManager instance to remove the OnClientConnectedCallback subscription
+                m_CachedNetworkManager = NetworkManager;
+                NetworkManager.OnClientConnectedCallback += OnClientConnectedCallback;
+            }
+            // We initialize the m_AnimationMessage for all instances in the event that
+            // ownership or authority changes during runtime.
+            m_AnimationMessage = new AnimationMessage();
+            m_AnimationMessage.AnimationStates = new List<AnimationState>();
 
-                // Store off our current layer weights
-                for (int layer = 0; layer < m_Animator.layerCount; layer++)
+            // Store off our current layer weights and create our animation
+            // state entries per layer.
+            for (int layer = 0; layer < m_Animator.layerCount; layer++)
+            {
+                // We create an AnimationState per layer to preallocate the maximum
+                // number of possible AnimationState changes we could send in one
+                // AnimationMessage.
+                m_AnimationMessage.AnimationStates.Add(new AnimationState());
+                float layerWeightNow = m_Animator.GetLayerWeight(layer);
+                if (layerWeightNow != m_LayerWeights[layer])
                 {
-                    float layerWeightNow = m_Animator.GetLayerWeight(layer);
-                    if (layerWeightNow != m_LayerWeights[layer])
-                    {
-                        m_LayerWeights[layer] = layerWeightNow;
-                    }
-                }
-
-                if (IsServer)
-                {
-                    m_ClientSendList = new List<ulong>(128);
-                    m_ClientRpcParams = new ClientRpcParams();
-                    m_ClientRpcParams.Send = new ClientRpcSendParams();
-                    m_ClientRpcParams.Send.TargetClientIds = m_ClientSendList;
+                    m_LayerWeights[layer] = layerWeightNow;
                 }
             }
 
+            // Build our reference parameter values to detect when they change
             var parameters = m_Animator.parameters;
             m_CachedAnimatorParameters = new NativeArray<AnimatorParamCache>(parameters.Length, Allocator.Persistent);
             m_ParametersToUpdate = new List<int>(parameters.Length);
@@ -372,6 +655,7 @@ namespace Unity.Netcode.Components
             m_NetworkAnimatorStateChangeHandler = new NetworkAnimatorStateChangeHandler(this);
         }
 
+        /// <inheritdoc/>
         public override void OnNetworkDespawn()
         {
             Cleanup();
@@ -392,18 +676,25 @@ namespace Unity.Netcode.Components
                 m_ParametersToUpdate.Add(i);
             }
             SendParametersUpdate(m_ClientRpcParams);
+
+            // Reset the dirty count before synchronizing the newly connected client with all layers
+            m_AnimationMessage.IsDirtyCount = 0;
+
             for (int layer = 0; layer < m_Animator.layerCount; layer++)
             {
                 AnimatorStateInfo st = m_Animator.GetCurrentAnimatorStateInfo(layer);
-
                 var stateHash = st.fullPathHash;
                 var normalizedTime = st.normalizedTime;
-                var totalSpeed = st.speed * st.speedMultiplier;
-                var adjustedNormalizedMaxTime = totalSpeed > 0.0f ? 1.0f / totalSpeed : 0.0f;
-                // NOTE:
-                // When synchronizing, for now we will just complete the transition and
-                // synchronize the player to the next state being transitioned into
-                if (m_Animator.IsInTransition(layer))
+                var isInTransition = m_Animator.IsInTransition(layer);
+
+                // Grab one of the available AnimationState entries so we can fill it with the current
+                // layer's animation state.
+                var animationState = m_AnimationMessage.AnimationStates[layer];
+
+                // Synchronizing transitions with trigger conditions for late joining clients is now
+                // handled by cross fading between the late joining client's current layer's AnimationState
+                // and the transition's destination AnimationState.
+                if (isInTransition)
                 {
                     var tt = m_Animator.GetAnimatorTransitionInfo(layer);
                     var nextState = m_Animator.GetNextAnimatorStateInfo(layer);
@@ -421,32 +712,47 @@ namespace Unity.Netcode.Components
                     {
                         normalizedTime = 0.0f;
                     }
-
                     stateHash = nextState.fullPathHash;
-                }
-                else
-                if (st.normalizedTime >= adjustedNormalizedMaxTime)
-                {
-                    continue;
+
+                    // Use the destination state to transition info lookup table to see if this is a transition we can
+                    // synchronize using cross fading
+                    if (m_DestinationStateToTransitioninfo.ContainsKey(layer))
+                    {
+                        if (m_DestinationStateToTransitioninfo[layer].ContainsKey(nextState.shortNameHash))
+                        {
+                            var destinationInfo = m_DestinationStateToTransitioninfo[layer][nextState.shortNameHash];
+                            stateHash = destinationInfo.OriginatingState;
+                            // Set the destination state to cross fade to from the originating state
+                            animationState.DestinationStateHash = destinationInfo.DestinationState;
+                        }
+                    }
                 }
 
-                var animMsg = new AnimationMessage
-                {
-                    StateHash = stateHash,
-                    NormalizedTime = normalizedTime,
-                    Layer = layer,
-                    Weight = m_LayerWeights[layer]
-                };
-                // Server always send via client RPC
-                SendAnimStateClientRpc(animMsg, m_ClientRpcParams);
+                animationState.Transition = isInTransition;        // The only time this could be set to true
+                animationState.StateHash = stateHash;              // When a transition, this is the originating/starting state
+                animationState.NormalizedTime = normalizedTime;
+                animationState.Layer = layer;
+                animationState.Weight = m_LayerWeights[layer];
+
+                // Apply the changes
+                m_AnimationMessage.AnimationStates[layer] = animationState;
             }
+            // Send all animation states
+            m_AnimationMessage.IsDirtyCount = m_Animator.layerCount;
+            SendAnimStateClientRpc(m_AnimationMessage, m_ClientRpcParams);
         }
 
+        /// <summary>
+        /// Required for the server to synchronize newly joining players
+        /// </summary>
         private void OnClientConnectedCallback(ulong playerId)
         {
             m_NetworkAnimatorStateChangeHandler.SynchronizeClient(playerId);
         }
 
+        /// <summary>
+        /// Checks for changes in both Animator parameters and state.
+        /// </summary>
         internal void CheckForAnimatorChanges()
         {
             if (!IsOwner && !IsServerAuthoritative() || IsServerAuthoritative() && !IsServer)
@@ -461,45 +767,57 @@ namespace Unity.Netcode.Components
 
             if (m_Animator.runtimeAnimatorController == null)
             {
+                if (NetworkManager.LogLevel == LogLevel.Developer)
+                {
+                    Debug.LogError($"[{GetType().Name}] Could not find an assigned {nameof(RuntimeAnimatorController)}! Cannot check {nameof(Animator)} for changes in state!");
+                }
                 return;
             }
 
             int stateHash;
             float normalizedTime;
 
-            // This sends updates only if a layer change or transition is happening
+            // Reset the dirty count before checking for AnimationState updates
+            m_AnimationMessage.IsDirtyCount = 0;
+
+            // This sends updates only if a layer's state has changed
             for (int layer = 0; layer < m_Animator.layerCount; layer++)
             {
                 AnimatorStateInfo st = m_Animator.GetCurrentAnimatorStateInfo(layer);
                 var totalSpeed = st.speed * st.speedMultiplier;
                 var adjustedNormalizedMaxTime = totalSpeed > 0.0f ? 1.0f / totalSpeed : 0.0f;
 
-                // determine if we have reached the end of our state time, if so we can skip
-                if (st.normalizedTime >= adjustedNormalizedMaxTime)
-                {
-                    continue;
-                }
-
                 if (!CheckAnimStateChanged(out stateHash, out normalizedTime, layer))
                 {
                     continue;
                 }
 
-                var animMsg = new AnimationMessage
-                {
-                    StateHash = stateHash,
-                    NormalizedTime = normalizedTime,
-                    Layer = layer,
-                    Weight = m_LayerWeights[layer]
-                };
+                // If we made it here, then we need to synchronize this layer's animation state.
+                // Get one of the preallocated AnimationState entries and populate it with the
+                // current layer's state.
+                var animationState = m_AnimationMessage.AnimationStates[m_AnimationMessage.IsDirtyCount];
 
+                animationState.Transition = false; // Only used during synchronization
+                animationState.StateHash = stateHash;
+                animationState.NormalizedTime = normalizedTime;
+                animationState.Layer = layer;
+                animationState.Weight = m_LayerWeights[layer];
+
+                // Apply the changes
+                m_AnimationMessage.AnimationStates[m_AnimationMessage.IsDirtyCount] = animationState;
+                m_AnimationMessage.IsDirtyCount++;
+            }
+
+            // Send an AnimationMessage only if there are dirty AnimationStates to send
+            if (m_AnimationMessage.IsDirtyCount > 0)
+            {
                 if (!IsServer && IsOwner)
                 {
-                    SendAnimStateServerRpc(animMsg);
+                    SendAnimStateServerRpc(m_AnimationMessage);
                 }
                 else
                 {
-                    SendAnimStateClientRpc(animMsg);
+                    SendAnimStateClientRpc(m_AnimationMessage);
                 }
             }
         }
@@ -595,7 +913,7 @@ namespace Unity.Netcode.Components
         /// <summary>
         /// Checks if any of the Animator's states have changed
         /// </summary>
-        private unsafe bool CheckAnimStateChanged(out int stateHash, out float normalizedTime, int layer)
+        private bool CheckAnimStateChanged(out int stateHash, out float normalizedTime, int layer)
         {
             stateHash = 0;
             normalizedTime = 0;
@@ -745,13 +1063,56 @@ namespace Unity.Netcode.Components
         }
 
         /// <summary>
-        /// Applies the AnimationMessage state to the Animator
+        /// Applies the AnimationState state to the Animator
         /// </summary>
-        private unsafe void UpdateAnimationState(AnimationMessage animationState)
+        internal void UpdateAnimationState(AnimationState animationState)
         {
-            if (animationState.StateHash != 0)
+            if (animationState.StateHash == 0)
             {
-                m_Animator.Play(animationState.StateHash, animationState.Layer, animationState.NormalizedTime);
+                return;
+            }
+
+            var currentState = m_Animator.GetCurrentAnimatorStateInfo(animationState.Layer);
+            // If it is a transition, then we are synchronizing transitions in progress when a client late joins
+            if (animationState.Transition)
+            {
+                // We should have all valid entries for any animation state transition update
+                // Verify the AnimationState's assigned Layer exists
+                if (m_DestinationStateToTransitioninfo.ContainsKey(animationState.Layer))
+                {
+                    // Verify the inner-table has the destination AnimationState name hash
+                    if (m_DestinationStateToTransitioninfo[animationState.Layer].ContainsKey(animationState.DestinationStateHash))
+                    {
+                        // Make sure we are on the originating/starting state we are going to cross fade into
+                        if (currentState.shortNameHash == animationState.StateHash)
+                        {
+                            // Get the transition state information
+                            var transitionStateInfo = m_DestinationStateToTransitioninfo[animationState.Layer][animationState.DestinationStateHash];
+
+                            // Cross fade from the current to the destination state for the transitions duration while starting at the server's current normalized time of the transition
+                            m_Animator.CrossFade(transitionStateInfo.DestinationState, transitionStateInfo.TransitionDuration, transitionStateInfo.Layer, 0.0f, animationState.NormalizedTime);
+                        }
+                        else if (NetworkManager.LogLevel == LogLevel.Developer)
+                        {
+                            NetworkLog.LogWarning($"Current State Hash ({currentState.fullPathHash}) != AnimationState.StateHash ({animationState.StateHash})");
+                        }
+                    }
+                    else if (NetworkManager.LogLevel == LogLevel.Developer)
+                    {
+                        NetworkLog.LogError($"[DestinationState To Transition Info] Layer ({animationState.Layer}) sub-table does not contain destination state ({animationState.DestinationStateHash})!");
+                    }
+                }
+                else if (NetworkManager.LogLevel == LogLevel.Developer)
+                {
+                    NetworkLog.LogError($"[DestinationState To Transition Info] Layer ({animationState.Layer}) does not exist!");
+                }
+            }
+            else
+            {
+                if (currentState.fullPathHash != animationState.StateHash)
+                {
+                    m_Animator.Play(animationState.StateHash, animationState.Layer, animationState.NormalizedTime);
+                }
             }
             m_Animator.SetLayerWeight(animationState.Layer, animationState.Weight);
         }
@@ -774,7 +1135,7 @@ namespace Unity.Netcode.Components
                     return;
                 }
                 UpdateParameters(parametersUpdate);
-                if (NetworkManager.ConnectedClientsIds.Count - 2 > 0)
+                if (NetworkManager.ConnectedClientsIds.Count > (IsHost ? 2 : 1))
                 {
                     m_ClientSendList.Clear();
                     m_ClientSendList.AddRange(NetworkManager.ConnectedClientsIds);
@@ -804,11 +1165,11 @@ namespace Unity.Netcode.Components
         /// The server sets its local state and then forwards the message to the remaining clients
         /// </summary>
         [ServerRpc]
-        private unsafe void SendAnimStateServerRpc(AnimationMessage animSnapshot, ServerRpcParams serverRpcParams = default)
+        private unsafe void SendAnimStateServerRpc(AnimationMessage animationMessage, ServerRpcParams serverRpcParams = default)
         {
             if (IsServerAuthoritative())
             {
-                m_NetworkAnimatorStateChangeHandler.SendAnimationUpdate(animSnapshot);
+                m_NetworkAnimatorStateChangeHandler.SendAnimationUpdate(animationMessage);
             }
             else
             {
@@ -816,15 +1177,21 @@ namespace Unity.Netcode.Components
                 {
                     return;
                 }
-                UpdateAnimationState(animSnapshot);
-                if (NetworkManager.ConnectedClientsIds.Count - 2 > 0)
+
+                foreach (var animationState in animationMessage.AnimationStates)
+                {
+                    UpdateAnimationState(animationState);
+                }
+
+                m_NetworkAnimatorStateChangeHandler.AddAnimationMessageToProcessQueue(animationMessage);
+                if (NetworkManager.ConnectedClientsIds.Count > (IsHost ? 2 : 1))
                 {
                     m_ClientSendList.Clear();
                     m_ClientSendList.AddRange(NetworkManager.ConnectedClientsIds);
                     m_ClientSendList.Remove(serverRpcParams.Receive.SenderClientId);
                     m_ClientSendList.Remove(NetworkManager.ServerClientId);
                     m_ClientRpcParams.Send.TargetClientIds = m_ClientSendList;
-                    m_NetworkAnimatorStateChangeHandler.SendAnimationUpdate(animSnapshot, m_ClientRpcParams);
+                    m_NetworkAnimatorStateChangeHandler.SendAnimationUpdate(animationMessage, m_ClientRpcParams);
                 }
             }
         }
@@ -833,12 +1200,25 @@ namespace Unity.Netcode.Components
         /// Internally-called RPC client receiving function to update some animation state on a client
         /// </summary>
         [ClientRpc]
-        private unsafe void SendAnimStateClientRpc(AnimationMessage animSnapshot, ClientRpcParams clientRpcParams = default)
+        private unsafe void SendAnimStateClientRpc(AnimationMessage animationMessage, ClientRpcParams clientRpcParams = default)
         {
+            // This should never happen
+            if (IsHost)
+            {
+                if (NetworkManager.LogLevel == LogLevel.Developer)
+                {
+                    NetworkLog.LogWarning("Detected the Host is sending itself animation updates! Please report this issue.");
+                }
+                return;
+            }
+
             var isServerAuthoritative = IsServerAuthoritative();
             if (!isServerAuthoritative && !IsOwner || isServerAuthoritative)
             {
-                UpdateAnimationState(animSnapshot);
+                foreach (var animationState in animationMessage.AnimationStates)
+                {
+                    UpdateAnimationState(animationState);
+                }
             }
         }
 
@@ -847,48 +1227,67 @@ namespace Unity.Netcode.Components
         /// The server sets its local state and then forwards the message to the remaining clients
         /// </summary>
         [ServerRpc]
-        private void SendAnimTriggerServerRpc(AnimationTriggerMessage animationTriggerMessage, ServerRpcParams serverRpcParams = default)
+        internal void SendAnimTriggerServerRpc(AnimationTriggerMessage animationTriggerMessage, ServerRpcParams serverRpcParams = default)
         {
+            // If it is server authoritative
             if (IsServerAuthoritative())
             {
-                m_NetworkAnimatorStateChangeHandler.SendTriggerUpdate(animationTriggerMessage);
+                // The only condition where this should (be allowed to) happen is when the owner sends the server a trigger message
+                if (OwnerClientId == serverRpcParams.Receive.SenderClientId)
+                {
+                    m_NetworkAnimatorStateChangeHandler.QueueTriggerUpdateToClient(animationTriggerMessage);
+                }
+                else if (NetworkManager.LogLevel == LogLevel.Developer)
+                {
+                    NetworkLog.LogWarning($"[Server Authoritative] Detected the a non-authoritative client is sending the server animation trigger updates. If you recently changed ownership of the {name} object, then this could be the reason.");
+                }
             }
             else
             {
+                // Ignore if a non-owner sent this.
                 if (serverRpcParams.Receive.SenderClientId != OwnerClientId)
                 {
+                    if (NetworkManager.LogLevel == LogLevel.Developer)
+                    {
+                        NetworkLog.LogWarning($"[Owner Authoritative] Detected the a non-authoritative client is sending the server animation trigger updates. If you recently changed ownership of the {name} object, then this could be the reason.");
+                    }
                     return;
                 }
-                //  trigger the animation locally on the server...
-                m_Animator.SetBool(animationTriggerMessage.Hash, animationTriggerMessage.IsTriggerSet);
 
-                if (NetworkManager.ConnectedClientsIds.Count - 2 > 0)
+                // set the trigger locally on the server
+                InternalSetTrigger(animationTriggerMessage.Hash, animationTriggerMessage.IsTriggerSet);
+
+                // send the message to all non-authority clients excluding the server and the owner
+                if (NetworkManager.ConnectedClientsIds.Count > (IsHost ? 2 : 1))
                 {
                     m_ClientSendList.Clear();
                     m_ClientSendList.AddRange(NetworkManager.ConnectedClientsIds);
                     m_ClientSendList.Remove(serverRpcParams.Receive.SenderClientId);
                     m_ClientSendList.Remove(NetworkManager.ServerClientId);
                     m_ClientRpcParams.Send.TargetClientIds = m_ClientSendList;
-                    m_NetworkAnimatorStateChangeHandler.SendTriggerUpdate(animationTriggerMessage, m_ClientRpcParams);
+                    m_NetworkAnimatorStateChangeHandler.QueueTriggerUpdateToClient(animationTriggerMessage, m_ClientRpcParams);
                 }
             }
+        }
 
+        /// <summary>
+        /// See above <see cref="m_LastTriggerHash"/>
+        /// </summary>
+        private void InternalSetTrigger(int hash, bool isSet = true)
+        {
+            m_Animator.SetBool(hash, isSet);
         }
 
         /// <summary>
         /// Internally-called RPC client receiving function to update a trigger when the server wants to forward
         ///   a trigger for a client to play / reset
         /// </summary>
-        /// <param name="animSnapshot">the payload containing the trigger data to apply</param>
+        /// <param name="animationTriggerMessage">the payload containing the trigger data to apply</param>
         /// <param name="clientRpcParams">unused</param>
         [ClientRpc]
         internal void SendAnimTriggerClientRpc(AnimationTriggerMessage animationTriggerMessage, ClientRpcParams clientRpcParams = default)
         {
-            var isServerAuthoritative = IsServerAuthoritative();
-            if (!isServerAuthoritative && !IsOwner || isServerAuthoritative)
-            {
-                m_Animator.SetBool(animationTriggerMessage.Hash, animationTriggerMessage.IsTriggerSet);
-            }
+            InternalSetTrigger(animationTriggerMessage.Hash, animationTriggerMessage.IsTriggerSet);
         }
 
         /// <summary>
@@ -905,20 +1304,33 @@ namespace Unity.Netcode.Components
         /// <param name="setTrigger">sets (true) or resets (false) the trigger. The default is to set it (true).</param>
         public void SetTrigger(int hash, bool setTrigger = true)
         {
-            var isServerAuthoritative = IsServerAuthoritative();
-            if (IsOwner && !isServerAuthoritative || IsServer && isServerAuthoritative)
+            // MTT-3564:
+            // After fixing the issue with trigger controlled Transitions being synchronized twice,
+            // it exposed additional issues with this logic.  Now, either the owner or the server can
+            // update triggers. Since server-side RPCs are immediately invoked, for a host a trigger
+            // will happen when SendAnimTriggerClientRpc is called.  For a client owner, we call the
+            // SendAnimTriggerServerRpc and then trigger locally when running in owner authority mode.
+            if (IsOwner || IsServer)
             {
                 var animTriggerMessage = new AnimationTriggerMessage() { Hash = hash, IsTriggerSet = setTrigger };
                 if (IsServer)
                 {
-                    SendAnimTriggerClientRpc(animTriggerMessage);
+                    /// <see cref="UpdatePendingTriggerStates"/> as to why we queue
+                    m_NetworkAnimatorStateChangeHandler.QueueTriggerUpdateToClient(animTriggerMessage);
+                    if (!IsHost)
+                    {
+                        InternalSetTrigger(hash);
+                    }
                 }
                 else
                 {
-                    SendAnimTriggerServerRpc(animTriggerMessage);
+                    /// <see cref="UpdatePendingTriggerStates"/> as to why we queue
+                    m_NetworkAnimatorStateChangeHandler.QueueTriggerUpdateToServer(animTriggerMessage);
+                    if (!IsServerAuthoritative())
+                    {
+                        InternalSetTrigger(hash);
+                    }
                 }
-                //  trigger the animation locally on the server...
-                m_Animator.SetBool(hash, setTrigger);
             }
         }
 

Components/NetworkRigidbody.cs

@@ -9,6 +9,7 @@ namespace Unity.Netcode.Components
     /// </summary>
     [RequireComponent(typeof(Rigidbody))]
     [RequireComponent(typeof(NetworkTransform))]
+    [AddComponentMenu("Netcode/Network Rigidbody")]
     public class NetworkRigidbody : NetworkBehaviour
     {
         /// <summary>

Components/NetworkRigidbody2D.cs

@@ -9,6 +9,7 @@ namespace Unity.Netcode.Components
     /// </summary>
     [RequireComponent(typeof(Rigidbody2D))]
     [RequireComponent(typeof(NetworkTransform))]
+    [AddComponentMenu("Netcode/Network Rigidbody 2D")]
     public class NetworkRigidbody2D : NetworkBehaviour
     {
         private Rigidbody2D m_Rigidbody;

Editor/CodeGen/CodeGenHelpers.cs

@@ -15,6 +15,10 @@ namespace Unity.Netcode.Editor.CodeGen
 {
     internal static class CodeGenHelpers
     {
+        public const string DotnetModuleName = "netstandard.dll";
+        public const string UnityModuleName = "UnityEngine.CoreModule.dll";
+        public const string NetcodeModuleName = "Unity.Netcode.Runtime.dll";
+
         public const string RuntimeAssemblyName = "Unity.Netcode.Runtime";
 
         public static readonly string NetworkBehaviour_FullName = typeof(NetworkBehaviour).FullName;
@@ -119,6 +123,19 @@ namespace Unity.Netcode.Editor.CodeGen
             try
             {
                 var typeDef = typeReference.Resolve();
+                // Note: this won't catch generics correctly.
+                //
+                //     class Foo<T>: IInterface<T> {}
+                //     class Bar: Foo<int> {}
+                //
+                // Bar.HasInterface(IInterface<int>) -> returns false even though it should be true.
+                //
+                // This can be fixed (see GetAllFieldsAndResolveGenerics() in NetworkBehaviourILPP to understand how)
+                // but right now we don't need that to work so it's left alone to reduce complexity
+                if (typeDef.BaseType.HasInterface(interfaceTypeFullName))
+                {
+                    return true;
+                }
                 var typeFaces = typeDef.Interfaces;
                 return typeFaces.Any(iface => iface.InterfaceType.FullName == interfaceTypeFullName);
             }
@@ -380,5 +397,74 @@ namespace Unity.Netcode.Editor.CodeGen
 
             return assemblyDefinition;
         }
+
+        private static void SearchForBaseModulesRecursive(AssemblyDefinition assemblyDefinition, PostProcessorAssemblyResolver assemblyResolver, ref ModuleDefinition unityModule, ref ModuleDefinition netcodeModule, HashSet<string> visited)
+        {
+
+            foreach (var module in assemblyDefinition.Modules)
+            {
+                if (module == null)
+                {
+                    continue;
+                }
+
+                if (unityModule != null && netcodeModule != null)
+                {
+                    return;
+                }
+
+                if (unityModule == null && module.Name == UnityModuleName)
+                {
+                    unityModule = module;
+                    continue;
+                }
+
+                if (netcodeModule == null && module.Name == NetcodeModuleName)
+                {
+                    netcodeModule = module;
+                    continue;
+                }
+            }
+            if (unityModule != null && netcodeModule != null)
+            {
+                return;
+            }
+
+            foreach (var assemblyNameReference in assemblyDefinition.MainModule.AssemblyReferences)
+            {
+                if (assemblyNameReference == null)
+                {
+                    continue;
+                }
+                if (visited.Contains(assemblyNameReference.Name))
+                {
+                    continue;
+                }
+
+                visited.Add(assemblyNameReference.Name);
+
+                var assembly = assemblyResolver.Resolve(assemblyNameReference);
+                if (assembly == null)
+                {
+                    continue;
+                }
+                SearchForBaseModulesRecursive(assembly, assemblyResolver, ref unityModule, ref netcodeModule, visited);
+
+                if (unityModule != null && netcodeModule != null)
+                {
+                    return;
+                }
+            }
+        }
+
+        public static (ModuleDefinition UnityModule, ModuleDefinition NetcodeModule) FindBaseModules(AssemblyDefinition assemblyDefinition, PostProcessorAssemblyResolver assemblyResolver)
+        {
+            ModuleDefinition unityModule = null;
+            ModuleDefinition netcodeModule = null;
+            var visited = new HashSet<string>();
+            SearchForBaseModulesRecursive(assemblyDefinition, assemblyResolver, ref unityModule, ref netcodeModule, visited);
+
+            return (unityModule, netcodeModule);
+        }
     }
 }

Editor/CodeGen/INetworkMessageILPP.cs

@@ -2,7 +2,6 @@ using System;
 using System.IO;
 using System.Linq;
 using System.Collections.Generic;
-using System.Reflection;
 using Mono.Cecil;
 using Mono.Cecil.Cil;
 using Mono.Cecil.Rocks;
@@ -17,9 +16,7 @@ namespace Unity.Netcode.Editor.CodeGen
     {
         public override ILPPInterface GetInstance() => this;
 
-        public override bool WillProcess(ICompiledAssembly compiledAssembly) =>
-            compiledAssembly.Name == CodeGenHelpers.RuntimeAssemblyName ||
-            compiledAssembly.References.Any(filePath => Path.GetFileNameWithoutExtension(filePath) == CodeGenHelpers.RuntimeAssemblyName);
+        public override bool WillProcess(ICompiledAssembly compiledAssembly) => compiledAssembly.Name == CodeGenHelpers.RuntimeAssemblyName;
 
         private readonly List<DiagnosticMessage> m_Diagnostics = new List<DiagnosticMessage>();
 
@@ -33,13 +30,22 @@ namespace Unity.Netcode.Editor.CodeGen
             m_Diagnostics.Clear();
 
             // read
-            var assemblyDefinition = CodeGenHelpers.AssemblyDefinitionFor(compiledAssembly, out var resolver);
+            var assemblyDefinition = CodeGenHelpers.AssemblyDefinitionFor(compiledAssembly, out m_AssemblyResolver);
             if (assemblyDefinition == null)
             {
                 m_Diagnostics.AddError($"Cannot read assembly definition: {compiledAssembly.Name}");
                 return null;
             }
 
+            // modules
+            (_, m_NetcodeModule) = CodeGenHelpers.FindBaseModules(assemblyDefinition, m_AssemblyResolver);
+
+            if (m_NetcodeModule == null)
+            {
+                m_Diagnostics.AddError($"Cannot find Netcode module: {CodeGenHelpers.NetcodeModuleName}");
+                return null;
+            }
+
             // process
             var mainModule = assemblyDefinition.MainModule;
             if (mainModule != null)
@@ -61,7 +67,7 @@ namespace Unity.Netcode.Editor.CodeGen
                     }
                     catch (Exception e)
                     {
-                        m_Diagnostics.AddError((e.ToString() + e.StackTrace.ToString()).Replace("\n", "|").Replace("\r", "|"));
+                        m_Diagnostics.AddError((e.ToString() + e.StackTrace).Replace("\n", "|").Replace("\r", "|"));
                     }
                 }
                 else
@@ -92,6 +98,8 @@ namespace Unity.Netcode.Editor.CodeGen
             return new ILPostProcessResult(new InMemoryAssembly(pe.ToArray(), pdb.ToArray()), m_Diagnostics);
         }
 
+        private ModuleDefinition m_NetcodeModule;
+        private PostProcessorAssemblyResolver m_AssemblyResolver;
 
         private MethodReference m_MessagingSystem_ReceiveMessage_MethodRef;
         private TypeReference m_MessagingSystem_MessageWithHandler_TypeRef;
@@ -106,63 +114,102 @@ namespace Unity.Netcode.Editor.CodeGen
 
         private bool ImportReferences(ModuleDefinition moduleDefinition)
         {
-            m_MessagingSystem_MessageHandler_Constructor_TypeRef = moduleDefinition.ImportReference(typeof(MessagingSystem.MessageHandler).GetConstructors()[0]);
+            // Different environments seem to have different situations...
+            // Some have these definitions in netstandard.dll...
+            // some seem to have them elsewhere...
+            // Since they're standard .net classes they're not going to cause
+            // the same issues as referencing other assemblies, in theory, since
+            // the definitions should be standard and consistent across platforms
+            // (i.e., there's no #if UNITY_EDITOR in them that could create
+            // invalid IL code)
+            TypeDefinition typeTypeDef = moduleDefinition.ImportReference(typeof(Type)).Resolve();
+            TypeDefinition listTypeDef = moduleDefinition.ImportReference(typeof(List<>)).Resolve();
 
-            var messageWithHandlerType = typeof(MessagingSystem.MessageWithHandler);
-            m_MessagingSystem_MessageWithHandler_TypeRef = moduleDefinition.ImportReference(messageWithHandlerType);
-            foreach (var fieldInfo in messageWithHandlerType.GetFields())
+            TypeDefinition messageHandlerTypeDef = null;
+            TypeDefinition messageWithHandlerTypeDef = null;
+            TypeDefinition ilppMessageProviderTypeDef = null;
+            TypeDefinition messagingSystemTypeDef = null;
+            foreach (var netcodeTypeDef in m_NetcodeModule.GetAllTypes())
             {
-                switch (fieldInfo.Name)
+                if (messageHandlerTypeDef == null && netcodeTypeDef.Name == nameof(MessagingSystem.MessageHandler))
+                {
+                    messageHandlerTypeDef = netcodeTypeDef;
+                    continue;
+                }
+
+                if (messageWithHandlerTypeDef == null && netcodeTypeDef.Name == nameof(MessagingSystem.MessageWithHandler))
+                {
+                    messageWithHandlerTypeDef = netcodeTypeDef;
+                    continue;
+                }
+
+                if (ilppMessageProviderTypeDef == null && netcodeTypeDef.Name == nameof(ILPPMessageProvider))
+                {
+                    ilppMessageProviderTypeDef = netcodeTypeDef;
+                    continue;
+                }
+
+                if (messagingSystemTypeDef == null && netcodeTypeDef.Name == nameof(MessagingSystem))
+                {
+                    messagingSystemTypeDef = netcodeTypeDef;
+                    continue;
+                }
+            }
+
+            m_MessagingSystem_MessageHandler_Constructor_TypeRef = moduleDefinition.ImportReference(messageHandlerTypeDef.GetConstructors().First());
+
+            m_MessagingSystem_MessageWithHandler_TypeRef = moduleDefinition.ImportReference(messageWithHandlerTypeDef);
+            foreach (var fieldDef in messageWithHandlerTypeDef.Fields)
+            {
+                switch (fieldDef.Name)
                 {
                     case nameof(MessagingSystem.MessageWithHandler.MessageType):
-                        m_MessagingSystem_MessageWithHandler_MessageType_FieldRef = moduleDefinition.ImportReference(fieldInfo);
+                        m_MessagingSystem_MessageWithHandler_MessageType_FieldRef = moduleDefinition.ImportReference(fieldDef);
                         break;
                     case nameof(MessagingSystem.MessageWithHandler.Handler):
-                        m_MessagingSystem_MessageWithHandler_Handler_FieldRef = moduleDefinition.ImportReference(fieldInfo);
+                        m_MessagingSystem_MessageWithHandler_Handler_FieldRef = moduleDefinition.ImportReference(fieldDef);
                         break;
                 }
             }
 
-            var typeType = typeof(Type);
-            foreach (var methodInfo in typeType.GetMethods())
+            foreach (var methodDef in typeTypeDef.Methods)
             {
-                switch (methodInfo.Name)
+                switch (methodDef.Name)
                 {
                     case nameof(Type.GetTypeFromHandle):
-                        m_Type_GetTypeFromHandle_MethodRef = moduleDefinition.ImportReference(methodInfo);
+                        m_Type_GetTypeFromHandle_MethodRef = moduleDefinition.ImportReference(methodDef);
                         break;
                 }
             }
 
-            var ilppMessageProviderType = typeof(ILPPMessageProvider);
-            foreach (var fieldInfo in ilppMessageProviderType.GetFields(BindingFlags.Static | BindingFlags.NonPublic))
+            foreach (var fieldDef in ilppMessageProviderTypeDef.Fields)
             {
-                switch (fieldInfo.Name)
+                switch (fieldDef.Name)
                 {
                     case nameof(ILPPMessageProvider.__network_message_types):
-                        m_ILPPMessageProvider___network_message_types_FieldRef = moduleDefinition.ImportReference(fieldInfo);
+                        m_ILPPMessageProvider___network_message_types_FieldRef = moduleDefinition.ImportReference(fieldDef);
                         break;
                 }
             }
 
-            var listType = typeof(List<MessagingSystem.MessageWithHandler>);
-            foreach (var methodInfo in listType.GetMethods())
+            foreach (var methodDef in listTypeDef.Methods)
             {
-                switch (methodInfo.Name)
+                switch (methodDef.Name)
                 {
-                    case nameof(List<MessagingSystem.MessageWithHandler>.Add):
-                        m_List_Add_MethodRef = moduleDefinition.ImportReference(methodInfo);
+                    case "Add":
+                        m_List_Add_MethodRef = methodDef;
+                        m_List_Add_MethodRef.DeclaringType = listTypeDef.MakeGenericInstanceType(messageWithHandlerTypeDef);
+                        m_List_Add_MethodRef = moduleDefinition.ImportReference(m_List_Add_MethodRef);
                         break;
                 }
             }
 
-            var messagingSystemType = typeof(MessagingSystem);
-            foreach (var methodInfo in messagingSystemType.GetMethods(BindingFlags.Static | BindingFlags.NonPublic | BindingFlags.Public))
+            foreach (var methodDef in messagingSystemTypeDef.Methods)
             {
-                switch (methodInfo.Name)
+                switch (methodDef.Name)
                 {
                     case k_ReceiveMessageName:
-                        m_MessagingSystem_ReceiveMessage_MethodRef = moduleDefinition.ImportReference(methodInfo);
+                        m_MessagingSystem_ReceiveMessage_MethodRef = moduleDefinition.ImportReference(methodDef);
                         break;
                 }
             }
@@ -218,10 +265,8 @@ namespace Unity.Netcode.Editor.CodeGen
             instructions.Add(processor.Create(OpCodes.Callvirt, m_List_Add_MethodRef));
         }
 
-        // Creates a static module constructor (which is executed when the module is loaded) that registers all the
-        // message types in the assembly with MessagingSystem.
-        // This is the same behavior as annotating a static method with [ModuleInitializer] in standardized
-        // C# (that attribute doesn't exist in Unity, but the static module constructor still works)
+        // Creates a static module constructor (which is executed when the module is loaded) that registers all the message types in the assembly with MessagingSystem.
+        // This is the same behavior as annotating a static method with [ModuleInitializer] in standardized C# (that attribute doesn't exist in Unity, but the static module constructor still works).
         // https://docs.microsoft.com/en-us/dotnet/api/system.runtime.compilerservices.moduleinitializerattribute?view=net-5.0
         // https://web.archive.org/web/20100212140402/http://blogs.msdn.com/junfeng/archive/2005/11/19/494914.aspx
         private void CreateModuleInitializer(AssemblyDefinition assembly, List<TypeDefinition> networkMessageTypes)

Editor/CodeGen/INetworkSerializableILPP.cs

@@ -10,7 +10,6 @@ using ILPPInterface = Unity.CompilationPipeline.Common.ILPostProcessing.ILPostPr
 
 namespace Unity.Netcode.Editor.CodeGen
 {
-
     internal sealed class INetworkSerializableILPP : ILPPInterface
     {
         public override ILPPInterface GetInstance() => this;
@@ -92,7 +91,7 @@ namespace Unity.Netcode.Editor.CodeGen
                 }
                 catch (Exception e)
                 {
-                    m_Diagnostics.AddError((e.ToString() + e.StackTrace.ToString()).Replace("\n", "|").Replace("\r", "|"));
+                    m_Diagnostics.AddError((e.ToString() + e.StackTrace).Replace("\n", "|").Replace("\r", "|"));
                 }
             }
             else

Editor/CodeGen/NetworkBehaviourILPP.cs

@@ -2,7 +2,6 @@ using System;
 using System.IO;
 using System.Linq;
 using System.Collections.Generic;
-using System.Reflection;
 using System.Runtime.CompilerServices;
 using Mono.Cecil;
 using Mono.Cecil.Cil;
@@ -23,8 +22,7 @@ namespace Unity.Netcode.Editor.CodeGen
 
         public override ILPPInterface GetInstance() => this;
 
-        public override bool WillProcess(ICompiledAssembly compiledAssembly) =>
-            compiledAssembly.References.Any(filePath => Path.GetFileNameWithoutExtension(filePath) == CodeGenHelpers.RuntimeAssemblyName);
+        public override bool WillProcess(ICompiledAssembly compiledAssembly) => compiledAssembly.References.Any(filePath => Path.GetFileNameWithoutExtension(filePath) == CodeGenHelpers.RuntimeAssemblyName);
 
         private readonly List<DiagnosticMessage> m_Diagnostics = new List<DiagnosticMessage>();
 
@@ -35,7 +33,6 @@ namespace Unity.Netcode.Editor.CodeGen
                 return null;
             }
 
-
             m_Diagnostics.Clear();
 
             // read
@@ -46,11 +43,27 @@ namespace Unity.Netcode.Editor.CodeGen
                 return null;
             }
 
+            // modules
+            (m_UnityModule, m_NetcodeModule) = CodeGenHelpers.FindBaseModules(assemblyDefinition, m_AssemblyResolver);
+
+            if (m_UnityModule == null)
+            {
+                m_Diagnostics.AddError($"Cannot find Unity module: {CodeGenHelpers.UnityModuleName}");
+                return null;
+            }
+
+            if (m_NetcodeModule == null)
+            {
+                m_Diagnostics.AddError($"Cannot find Netcode module: {CodeGenHelpers.NetcodeModuleName}");
+                return null;
+            }
+
             // process
             var mainModule = assemblyDefinition.MainModule;
             if (mainModule != null)
             {
                 m_MainModule = mainModule;
+
                 if (ImportReferences(mainModule))
                 {
                     // process `NetworkBehaviour` types
@@ -60,10 +73,12 @@ namespace Unity.Netcode.Editor.CodeGen
                             .Where(t => t.IsSubclassOf(CodeGenHelpers.NetworkBehaviour_FullName))
                             .ToList()
                             .ForEach(b => ProcessNetworkBehaviour(b, compiledAssembly.Defines));
+
+                        CreateNetworkVariableTypeInitializers(assemblyDefinition);
                     }
                     catch (Exception e)
                     {
-                        m_Diagnostics.AddError((e.ToString() + e.StackTrace.ToString()).Replace("\n", "|").Replace("\r", "|"));
+                        m_Diagnostics.AddError((e.ToString() + e.StackTrace).Replace("\n", "|").Replace("\r", "|"));
                     }
                 }
                 else
@@ -92,7 +107,117 @@ namespace Unity.Netcode.Editor.CodeGen
             return new ILPostProcessResult(new InMemoryAssembly(pe.ToArray(), pdb.ToArray()), m_Diagnostics);
         }
 
+        private MethodDefinition GetOrCreateStaticConstructor(TypeDefinition typeDefinition)
+        {
+            var staticCtorMethodDef = typeDefinition.GetStaticConstructor();
+            if (staticCtorMethodDef == null)
+            {
+                staticCtorMethodDef = new MethodDefinition(
+                    ".cctor", // Static Constructor (constant-constructor)
+                    MethodAttributes.HideBySig |
+                    MethodAttributes.SpecialName |
+                    MethodAttributes.RTSpecialName |
+                    MethodAttributes.Static,
+                    typeDefinition.Module.TypeSystem.Void);
+                staticCtorMethodDef.Body.Instructions.Add(Instruction.Create(OpCodes.Ret));
+                typeDefinition.Methods.Add(staticCtorMethodDef);
+            }
+
+            return staticCtorMethodDef;
+        }
+
+        private bool IsMemcpyableType(TypeReference type)
+        {
+            foreach (var supportedType in BaseSupportedTypes)
+            {
+                if (type.FullName == supportedType.FullName)
+                {
+                    return true;
+                }
+            }
+
+            return false;
+        }
+
+        private void CreateNetworkVariableTypeInitializers(AssemblyDefinition assembly)
+        {
+            foreach (var typeDefinition in assembly.MainModule.Types)
+            {
+                if (typeDefinition.FullName == "<Module>")
+                {
+                    var staticCtorMethodDef = GetOrCreateStaticConstructor(typeDefinition);
+
+                    var processor = staticCtorMethodDef.Body.GetILProcessor();
+
+                    var instructions = new List<Instruction>();
+
+                    foreach (var type in m_WrappedNetworkVariableTypes)
+                    {
+                        // If a serializable type isn't found, FallbackSerializer will be used automatically, which will
+                        // call into UserNetworkVariableSerialization, giving the user a chance to define their own serializaiton
+                        // for types that aren't in our official supported types list.
+                        GenericInstanceMethod serializeMethod = null;
+                        GenericInstanceMethod equalityMethod;
+
+                        if (type.IsValueType)
+                        {
+                            if (type.HasInterface(typeof(INetworkSerializeByMemcpy).FullName) || type.Resolve().IsEnum || IsMemcpyableType(type))
+                            {
+                                serializeMethod = new GenericInstanceMethod(m_NetworkVariableSerializationTypes_InitializeSerializer_UnmanagedByMemcpy_MethodRef);
+                            }
+                            else if (type.HasInterface(typeof(INetworkSerializable).FullName))
+                            {
+                                serializeMethod = new GenericInstanceMethod(m_NetworkVariableSerializationTypes_InitializeSerializer_UnmanagedINetworkSerializable_MethodRef);
+                            }
+                            else if (type.HasInterface(CodeGenHelpers.IUTF8Bytes_FullName) && type.HasInterface(k_INativeListBool_FullName))
+                            {
+                                serializeMethod = new GenericInstanceMethod(m_NetworkVariableSerializationTypes_InitializeSerializer_FixedString_MethodRef);
+                            }
+
+                            if (type.HasInterface(typeof(IEquatable<>).FullName + "<" + type.FullName + ">"))
+                            {
+                                equalityMethod = new GenericInstanceMethod(m_NetworkVariableSerializationTypes_InitializeEqualityChecker_UnmanagedIEquatable_MethodRef);
+                            }
+                            else
+                            {
+                                equalityMethod = new GenericInstanceMethod(m_NetworkVariableSerializationTypes_InitializeEqualityChecker_UnmanagedValueEquals_MethodRef);
+                            }
+                        }
+                        else
+                        {
+                            if (type.HasInterface(typeof(INetworkSerializable).FullName))
+                            {
+                                serializeMethod = new GenericInstanceMethod(m_NetworkVariableSerializationTypes_InitializeSerializer_ManagedINetworkSerializable_MethodRef);
+                            }
+
+                            if (type.HasInterface(typeof(IEquatable<>).FullName + "<" + type.FullName + ">"))
+                            {
+                                equalityMethod = new GenericInstanceMethod(m_NetworkVariableSerializationTypes_InitializeEqualityChecker_ManagedIEquatable_MethodRef);
+                            }
+                            else
+                            {
+                                equalityMethod = new GenericInstanceMethod(m_NetworkVariableSerializationTypes_InitializeEqualityChecker_ManagedClassEquals_MethodRef);
+                            }
+                        }
+
+                        if (serializeMethod != null)
+                        {
+                            serializeMethod.GenericArguments.Add(type);
+                            instructions.Add(processor.Create(OpCodes.Call, m_MainModule.ImportReference(serializeMethod)));
+                        }
+                        equalityMethod.GenericArguments.Add(type);
+                        instructions.Add(processor.Create(OpCodes.Call, m_MainModule.ImportReference(equalityMethod)));
+                    }
+
+                    instructions.ForEach(instruction => processor.Body.Instructions.Insert(processor.Body.Instructions.Count - 1, instruction));
+                    break;
+                }
+            }
+        }
+
         private ModuleDefinition m_MainModule;
+        private ModuleDefinition m_UnityModule;
+        private ModuleDefinition m_NetcodeModule;
         private PostProcessorAssemblyResolver m_AssemblyResolver;
 
         private MethodReference m_Debug_LogError_MethodRef;
@@ -123,14 +248,51 @@ namespace Unity.Netcode.Editor.CodeGen
         private FieldReference m_ServerRpcParams_Receive_FieldRef;
         private FieldReference m_ServerRpcParams_Receive_SenderClientId_FieldRef;
         private TypeReference m_ClientRpcParams_TypeRef;
+        private MethodReference m_NetworkVariableSerializationTypes_InitializeSerializer_UnmanagedByMemcpy_MethodRef;
+        private MethodReference m_NetworkVariableSerializationTypes_InitializeSerializer_UnmanagedINetworkSerializable_MethodRef;
+        private MethodReference m_NetworkVariableSerializationTypes_InitializeSerializer_ManagedINetworkSerializable_MethodRef;
+        private MethodReference m_NetworkVariableSerializationTypes_InitializeSerializer_FixedString_MethodRef;
+        private MethodReference m_NetworkVariableSerializationTypes_InitializeEqualityChecker_ManagedIEquatable_MethodRef;
+        private MethodReference m_NetworkVariableSerializationTypes_InitializeEqualityChecker_UnmanagedIEquatable_MethodRef;
+        private MethodReference m_NetworkVariableSerializationTypes_InitializeEqualityChecker_UnmanagedValueEquals_MethodRef;
+        private MethodReference m_NetworkVariableSerializationTypes_InitializeEqualityChecker_ManagedClassEquals_MethodRef;
 
         private TypeReference m_FastBufferWriter_TypeRef;
-        private Dictionary<string, MethodReference> m_FastBufferWriter_WriteValue_MethodRefs = new Dictionary<string, MethodReference>();
-        private List<MethodReference> m_FastBufferWriter_ExtensionMethodRefs = new List<MethodReference>();
+        private readonly Dictionary<string, MethodReference> m_FastBufferWriter_WriteValue_MethodRefs = new Dictionary<string, MethodReference>();
+        private readonly List<MethodReference> m_FastBufferWriter_ExtensionMethodRefs = new List<MethodReference>();
 
         private TypeReference m_FastBufferReader_TypeRef;
-        private Dictionary<string, MethodReference> m_FastBufferReader_ReadValue_MethodRefs = new Dictionary<string, MethodReference>();
-        private List<MethodReference> m_FastBufferReader_ExtensionMethodRefs = new List<MethodReference>();
+        private readonly Dictionary<string, MethodReference> m_FastBufferReader_ReadValue_MethodRefs = new Dictionary<string, MethodReference>();
+        private readonly List<MethodReference> m_FastBufferReader_ExtensionMethodRefs = new List<MethodReference>();
+
+        private HashSet<TypeReference> m_WrappedNetworkVariableTypes = new HashSet<TypeReference>();
+
+        internal static readonly Type[] BaseSupportedTypes = new[]
+        {
+            typeof(bool),
+            typeof(byte),
+            typeof(sbyte),
+            typeof(char),
+            typeof(decimal),
+            typeof(double),
+            typeof(float),
+            typeof(int),
+            typeof(uint),
+            typeof(long),
+            typeof(ulong),
+            typeof(short),
+            typeof(ushort),
+            typeof(Vector2),
+            typeof(Vector3),
+            typeof(Vector2Int),
+            typeof(Vector3Int),
+            typeof(Vector4),
+            typeof(Quaternion),
+            typeof(Color),
+            typeof(Color32),
+            typeof(Ray),
+            typeof(Ray2D)
+        };
 
         private const string k_Debug_LogError = nameof(Debug.LogError);
         private const string k_NetworkManager_LocalClientId = nameof(NetworkManager.LocalClientId);
@@ -157,160 +319,243 @@ namespace Unity.Netcode.Editor.CodeGen
         private const string k_ServerRpcParams_Receive = nameof(ServerRpcParams.Receive);
         private const string k_ServerRpcReceiveParams_SenderClientId = nameof(ServerRpcReceiveParams.SenderClientId);
 
+        // CodeGen cannot reference the collections assembly to do a typeof() on it due to a bug that causes that to crash.
+        private const string k_INativeListBool_FullName = "Unity.Collections.INativeList`1<System.Byte>";
+
         private bool ImportReferences(ModuleDefinition moduleDefinition)
         {
-            var debugType = typeof(Debug);
-            foreach (var methodInfo in debugType.GetMethods())
+            TypeDefinition debugTypeDef = null;
+            foreach (var unityTypeDef in m_UnityModule.GetAllTypes())
             {
-                switch (methodInfo.Name)
+                if (debugTypeDef == null && unityTypeDef.FullName == typeof(Debug).FullName)
+                {
+                    debugTypeDef = unityTypeDef;
+                    continue;
+                }
+            }
+
+            TypeDefinition networkManagerTypeDef = null;
+            TypeDefinition networkBehaviourTypeDef = null;
+            TypeDefinition networkHandlerDelegateTypeDef = null;
+            TypeDefinition rpcParamsTypeDef = null;
+            TypeDefinition serverRpcParamsTypeDef = null;
+            TypeDefinition clientRpcParamsTypeDef = null;
+            TypeDefinition fastBufferWriterTypeDef = null;
+            TypeDefinition fastBufferReaderTypeDef = null;
+            TypeDefinition networkVariableSerializationTypesTypeDef = null;
+            foreach (var netcodeTypeDef in m_NetcodeModule.GetAllTypes())
+            {
+                if (networkManagerTypeDef == null && netcodeTypeDef.Name == nameof(NetworkManager))
+                {
+                    networkManagerTypeDef = netcodeTypeDef;
+                    continue;
+                }
+
+                if (networkBehaviourTypeDef == null && netcodeTypeDef.Name == nameof(NetworkBehaviour))
+                {
+                    networkBehaviourTypeDef = netcodeTypeDef;
+                    continue;
+                }
+
+                if (networkHandlerDelegateTypeDef == null && netcodeTypeDef.Name == nameof(NetworkManager.RpcReceiveHandler))
+                {
+                    networkHandlerDelegateTypeDef = netcodeTypeDef;
+                    continue;
+                }
+
+                if (rpcParamsTypeDef == null && netcodeTypeDef.Name == nameof(__RpcParams))
+                {
+                    rpcParamsTypeDef = netcodeTypeDef;
+                    continue;
+                }
+
+                if (serverRpcParamsTypeDef == null && netcodeTypeDef.Name == nameof(ServerRpcParams))
+                {
+                    serverRpcParamsTypeDef = netcodeTypeDef;
+                    continue;
+                }
+
+                if (clientRpcParamsTypeDef == null && netcodeTypeDef.Name == nameof(ClientRpcParams))
+                {
+                    clientRpcParamsTypeDef = netcodeTypeDef;
+                    continue;
+                }
+
+                if (fastBufferWriterTypeDef == null && netcodeTypeDef.Name == nameof(FastBufferWriter))
+                {
+                    fastBufferWriterTypeDef = netcodeTypeDef;
+                    continue;
+                }
+
+                if (fastBufferReaderTypeDef == null && netcodeTypeDef.Name == nameof(FastBufferReader))
+                {
+                    fastBufferReaderTypeDef = netcodeTypeDef;
+                    continue;
+                }
+
+                if (networkVariableSerializationTypesTypeDef == null && netcodeTypeDef.Name == nameof(NetworkVariableSerializationTypes))
+                {
+                    networkVariableSerializationTypesTypeDef = netcodeTypeDef;
+                    continue;
+                }
+            }
+
+            foreach (var methodDef in debugTypeDef.Methods)
+            {
+                switch (methodDef.Name)
                 {
                     case k_Debug_LogError:
-                        if (methodInfo.GetParameters().Length == 1)
+                        if (methodDef.Parameters.Count == 1)
                         {
-                            m_Debug_LogError_MethodRef = moduleDefinition.ImportReference(methodInfo);
+                            m_Debug_LogError_MethodRef = moduleDefinition.ImportReference(methodDef);
                         }
 
                         break;
                 }
             }
 
-            var networkManagerType = typeof(NetworkManager);
-            m_NetworkManager_TypeRef = moduleDefinition.ImportReference(networkManagerType);
-            foreach (var propertyInfo in networkManagerType.GetProperties())
+            m_NetworkManager_TypeRef = moduleDefinition.ImportReference(networkManagerTypeDef);
+            foreach (var propertyDef in networkManagerTypeDef.Properties)
             {
-                switch (propertyInfo.Name)
+                switch (propertyDef.Name)
                 {
                     case k_NetworkManager_LocalClientId:
-                        m_NetworkManager_getLocalClientId_MethodRef = moduleDefinition.ImportReference(propertyInfo.GetMethod);
+                        m_NetworkManager_getLocalClientId_MethodRef = moduleDefinition.ImportReference(propertyDef.GetMethod);
                         break;
                     case k_NetworkManager_IsListening:
-                        m_NetworkManager_getIsListening_MethodRef = moduleDefinition.ImportReference(propertyInfo.GetMethod);
+                        m_NetworkManager_getIsListening_MethodRef = moduleDefinition.ImportReference(propertyDef.GetMethod);
                         break;
                     case k_NetworkManager_IsHost:
-                        m_NetworkManager_getIsHost_MethodRef = moduleDefinition.ImportReference(propertyInfo.GetMethod);
+                        m_NetworkManager_getIsHost_MethodRef = moduleDefinition.ImportReference(propertyDef.GetMethod);
                         break;
                     case k_NetworkManager_IsServer:
-                        m_NetworkManager_getIsServer_MethodRef = moduleDefinition.ImportReference(propertyInfo.GetMethod);
+                        m_NetworkManager_getIsServer_MethodRef = moduleDefinition.ImportReference(propertyDef.GetMethod);
                         break;
                     case k_NetworkManager_IsClient:
-                        m_NetworkManager_getIsClient_MethodRef = moduleDefinition.ImportReference(propertyInfo.GetMethod);
+                        m_NetworkManager_getIsClient_MethodRef = moduleDefinition.ImportReference(propertyDef.GetMethod);
                         break;
                 }
             }
 
-            foreach (var fieldInfo in networkManagerType.GetFields(BindingFlags.Static | BindingFlags.Instance | BindingFlags.NonPublic | BindingFlags.Public))
+            foreach (var fieldDef in networkManagerTypeDef.Fields)
             {
-                switch (fieldInfo.Name)
+                switch (fieldDef.Name)
                 {
                     case k_NetworkManager_LogLevel:
-                        m_NetworkManager_LogLevel_FieldRef = moduleDefinition.ImportReference(fieldInfo);
+                        m_NetworkManager_LogLevel_FieldRef = moduleDefinition.ImportReference(fieldDef);
                         break;
                     case k_NetworkManager_rpc_func_table:
-                        m_NetworkManager_rpc_func_table_FieldRef = moduleDefinition.ImportReference(fieldInfo);
-                        m_NetworkManager_rpc_func_table_Add_MethodRef = moduleDefinition.ImportReference(fieldInfo.FieldType.GetMethod("Add"));
+                        m_NetworkManager_rpc_func_table_FieldRef = moduleDefinition.ImportReference(fieldDef);
+
+                        m_NetworkManager_rpc_func_table_Add_MethodRef = fieldDef.FieldType.Resolve().Methods.First(m => m.Name == "Add");
+                        m_NetworkManager_rpc_func_table_Add_MethodRef.DeclaringType = fieldDef.FieldType;
+                        m_NetworkManager_rpc_func_table_Add_MethodRef = moduleDefinition.ImportReference(m_NetworkManager_rpc_func_table_Add_MethodRef);
                         break;
                     case k_NetworkManager_rpc_name_table:
-                        m_NetworkManager_rpc_name_table_FieldRef = moduleDefinition.ImportReference(fieldInfo);
-                        m_NetworkManager_rpc_name_table_Add_MethodRef = moduleDefinition.ImportReference(fieldInfo.FieldType.GetMethod("Add"));
+                        m_NetworkManager_rpc_name_table_FieldRef = moduleDefinition.ImportReference(fieldDef);
+
+                        m_NetworkManager_rpc_name_table_Add_MethodRef = fieldDef.FieldType.Resolve().Methods.First(m => m.Name == "Add");
+                        m_NetworkManager_rpc_name_table_Add_MethodRef.DeclaringType = fieldDef.FieldType;
+                        m_NetworkManager_rpc_name_table_Add_MethodRef = moduleDefinition.ImportReference(m_NetworkManager_rpc_name_table_Add_MethodRef);
                         break;
                 }
             }
 
-            var networkBehaviourType = typeof(NetworkBehaviour);
-            m_NetworkBehaviour_TypeRef = moduleDefinition.ImportReference(networkBehaviourType);
-            foreach (var propertyInfo in networkBehaviourType.GetProperties())
+            m_NetworkBehaviour_TypeRef = moduleDefinition.ImportReference(networkBehaviourTypeDef);
+            foreach (var propertyDef in networkBehaviourTypeDef.Properties)
             {
-                switch (propertyInfo.Name)
+                switch (propertyDef.Name)
                 {
                     case k_NetworkBehaviour_NetworkManager:
-                        m_NetworkBehaviour_getNetworkManager_MethodRef = moduleDefinition.ImportReference(propertyInfo.GetMethod);
+                        m_NetworkBehaviour_getNetworkManager_MethodRef = moduleDefinition.ImportReference(propertyDef.GetMethod);
                         break;
                     case k_NetworkBehaviour_OwnerClientId:
-                        m_NetworkBehaviour_getOwnerClientId_MethodRef = moduleDefinition.ImportReference(propertyInfo.GetMethod);
+                        m_NetworkBehaviour_getOwnerClientId_MethodRef = moduleDefinition.ImportReference(propertyDef.GetMethod);
                         break;
                 }
             }
 
-            foreach (var methodInfo in networkBehaviourType.GetMethods(BindingFlags.Static | BindingFlags.Instance | BindingFlags.NonPublic | BindingFlags.Public))
+            foreach (var methodDef in networkBehaviourTypeDef.Methods)
             {
-                switch (methodInfo.Name)
+                switch (methodDef.Name)
                 {
                     case k_NetworkBehaviour_beginSendServerRpc:
-                        m_NetworkBehaviour_beginSendServerRpc_MethodRef = moduleDefinition.ImportReference(methodInfo);
+                        m_NetworkBehaviour_beginSendServerRpc_MethodRef = moduleDefinition.ImportReference(methodDef);
                         break;
                     case k_NetworkBehaviour_endSendServerRpc:
-                        m_NetworkBehaviour_endSendServerRpc_MethodRef = moduleDefinition.ImportReference(methodInfo);
+                        m_NetworkBehaviour_endSendServerRpc_MethodRef = moduleDefinition.ImportReference(methodDef);
                         break;
                     case k_NetworkBehaviour_beginSendClientRpc:
-                        m_NetworkBehaviour_beginSendClientRpc_MethodRef = moduleDefinition.ImportReference(methodInfo);
+                        m_NetworkBehaviour_beginSendClientRpc_MethodRef = moduleDefinition.ImportReference(methodDef);
                         break;
                     case k_NetworkBehaviour_endSendClientRpc:
-                        m_NetworkBehaviour_endSendClientRpc_MethodRef = moduleDefinition.ImportReference(methodInfo);
+                        m_NetworkBehaviour_endSendClientRpc_MethodRef = moduleDefinition.ImportReference(methodDef);
                         break;
                 }
             }
 
-            foreach (var fieldInfo in networkBehaviourType.GetFields(BindingFlags.Instance | BindingFlags.NonPublic | BindingFlags.Public))
+            foreach (var fieldDef in networkBehaviourTypeDef.Fields)
             {
-                switch (fieldInfo.Name)
+                switch (fieldDef.Name)
                 {
                     case k_NetworkBehaviour_rpc_exec_stage:
-                        m_NetworkBehaviour_rpc_exec_stage_FieldRef = moduleDefinition.ImportReference(fieldInfo);
+                        m_NetworkBehaviour_rpc_exec_stage_FieldRef = moduleDefinition.ImportReference(fieldDef);
                         break;
                 }
             }
 
-            var networkHandlerDelegateType = typeof(NetworkManager.RpcReceiveHandler);
-            m_NetworkHandlerDelegateCtor_MethodRef = moduleDefinition.ImportReference(networkHandlerDelegateType.GetConstructor(new[] { typeof(object), typeof(IntPtr) }));
-
-            var rpcParamsType = typeof(__RpcParams);
-            m_RpcParams_TypeRef = moduleDefinition.ImportReference(rpcParamsType);
-            foreach (var fieldInfo in rpcParamsType.GetFields())
+            foreach (var ctor in networkHandlerDelegateTypeDef.Resolve().GetConstructors())
             {
-                switch (fieldInfo.Name)
+                if (ctor.HasParameters &&
+                    ctor.Parameters.Count == 2 &&
+                    ctor.Parameters[0].ParameterType.Name == nameof(System.Object) &&
+                    ctor.Parameters[1].ParameterType.Name == nameof(IntPtr))
+                {
+                    m_NetworkHandlerDelegateCtor_MethodRef = moduleDefinition.ImportReference(ctor);
+                    break;
+                }
+            }
+
+            m_RpcParams_TypeRef = moduleDefinition.ImportReference(rpcParamsTypeDef);
+            foreach (var fieldDef in rpcParamsTypeDef.Fields)
+            {
+                switch (fieldDef.Name)
                 {
                     case k_RpcParams_Server:
-                        m_RpcParams_Server_FieldRef = moduleDefinition.ImportReference(fieldInfo);
+                        m_RpcParams_Server_FieldRef = moduleDefinition.ImportReference(fieldDef);
                         break;
                     case k_RpcParams_Client:
-                        m_RpcParams_Client_FieldRef = moduleDefinition.ImportReference(fieldInfo);
+                        m_RpcParams_Client_FieldRef = moduleDefinition.ImportReference(fieldDef);
                         break;
                 }
             }
 
-            var serverRpcParamsType = typeof(ServerRpcParams);
-            m_ServerRpcParams_TypeRef = moduleDefinition.ImportReference(serverRpcParamsType);
-            foreach (var fieldInfo in serverRpcParamsType.GetFields())
+            m_ServerRpcParams_TypeRef = moduleDefinition.ImportReference(serverRpcParamsTypeDef);
+            foreach (var fieldDef in serverRpcParamsTypeDef.Fields)
             {
-                switch (fieldInfo.Name)
+                switch (fieldDef.Name)
                 {
                     case k_ServerRpcParams_Receive:
-                        foreach (var recvFieldInfo in fieldInfo.FieldType.GetFields())
+                        foreach (var recvFieldDef in fieldDef.FieldType.Resolve().Fields)
                         {
-                            switch (recvFieldInfo.Name)
+                            switch (recvFieldDef.Name)
                             {
                                 case k_ServerRpcReceiveParams_SenderClientId:
-                                    m_ServerRpcParams_Receive_SenderClientId_FieldRef = moduleDefinition.ImportReference(recvFieldInfo);
+                                    m_ServerRpcParams_Receive_SenderClientId_FieldRef = moduleDefinition.ImportReference(recvFieldDef);
                                     break;
                             }
                         }
 
-                        m_ServerRpcParams_Receive_FieldRef = moduleDefinition.ImportReference(fieldInfo);
+                        m_ServerRpcParams_Receive_FieldRef = moduleDefinition.ImportReference(fieldDef);
                         break;
                 }
             }
 
-            var clientRpcParamsType = typeof(ClientRpcParams);
-            m_ClientRpcParams_TypeRef = moduleDefinition.ImportReference(clientRpcParamsType);
+            m_ClientRpcParams_TypeRef = moduleDefinition.ImportReference(clientRpcParamsTypeDef);
+            m_FastBufferWriter_TypeRef = moduleDefinition.ImportReference(fastBufferWriterTypeDef);
+            m_FastBufferReader_TypeRef = moduleDefinition.ImportReference(fastBufferReaderTypeDef);
 
-            var fastBufferWriterType = typeof(FastBufferWriter);
-            m_FastBufferWriter_TypeRef = moduleDefinition.ImportReference(fastBufferWriterType);
-
-            var fastBufferReaderType = typeof(FastBufferReader);
-            m_FastBufferReader_TypeRef = moduleDefinition.ImportReference(fastBufferReaderType);
-
-            // Find all extension methods for FastBufferReader and FastBufferWriter to enable user-implemented
-            // methods to be called.
+            // Find all extension methods for FastBufferReader and FastBufferWriter to enable user-implemented methods to be called
             var assemblies = new List<AssemblyDefinition> { m_MainModule.Assembly };
             foreach (var reference in m_MainModule.AssemblyReferences)
             {
@@ -371,9 +616,94 @@ namespace Unity.Netcode.Editor.CodeGen
                 }
             }
 
+            foreach (var method in networkVariableSerializationTypesTypeDef.Methods)
+            {
+                if (!method.IsStatic)
+                {
+                    continue;
+                }
+
+                switch (method.Name)
+                {
+                    case nameof(NetworkVariableSerializationTypes.InitializeSerializer_UnmanagedByMemcpy):
+                        m_NetworkVariableSerializationTypes_InitializeSerializer_UnmanagedByMemcpy_MethodRef = method;
+                        break;
+                    case nameof(NetworkVariableSerializationTypes.InitializeSerializer_UnmanagedINetworkSerializable):
+                        m_NetworkVariableSerializationTypes_InitializeSerializer_UnmanagedINetworkSerializable_MethodRef = method;
+                        break;
+                    case nameof(NetworkVariableSerializationTypes.InitializeSerializer_ManagedINetworkSerializable):
+                        m_NetworkVariableSerializationTypes_InitializeSerializer_ManagedINetworkSerializable_MethodRef = method;
+                        break;
+                    case nameof(NetworkVariableSerializationTypes.InitializeSerializer_FixedString):
+                        m_NetworkVariableSerializationTypes_InitializeSerializer_FixedString_MethodRef = method;
+                        break;
+                    case nameof(NetworkVariableSerializationTypes.InitializeEqualityChecker_ManagedIEquatable):
+                        m_NetworkVariableSerializationTypes_InitializeEqualityChecker_ManagedIEquatable_MethodRef = method;
+                        break;
+                    case nameof(NetworkVariableSerializationTypes.InitializeEqualityChecker_UnmanagedIEquatable):
+                        m_NetworkVariableSerializationTypes_InitializeEqualityChecker_UnmanagedIEquatable_MethodRef = method;
+                        break;
+                    case nameof(NetworkVariableSerializationTypes.InitializeEqualityChecker_UnmanagedValueEquals):
+                        m_NetworkVariableSerializationTypes_InitializeEqualityChecker_UnmanagedValueEquals_MethodRef = method;
+                        break;
+                    case nameof(NetworkVariableSerializationTypes.InitializeEqualityChecker_ManagedClassEquals):
+                        m_NetworkVariableSerializationTypes_InitializeEqualityChecker_ManagedClassEquals_MethodRef = method;
+                        break;
+                }
+            }
+
             return true;
         }
 
+        // This gets all fields from this type as well as any parent types, up to (but not including) the base NetworkBehaviour class
+        // Importantly... this also resolves any generics, so if the base class is Foo<T> and contains a field of NetworkVariable<T>,
+        // and this class is Bar : Foo<int>, it will properly resolve NetworkVariable<T> to NetworkVariable<int>.
+        private void GetAllFieldsAndResolveGenerics(TypeDefinition type, ref List<TypeReference> fieldTypes, Dictionary<string, TypeReference> genericParameters = null)
+        {
+            foreach (var field in type.Fields)
+            {
+                if (field.FieldType.IsGenericInstance)
+                {
+                    var genericType = (GenericInstanceType)field.FieldType;
+                    var newGenericType = new GenericInstanceType(field.FieldType.Resolve());
+                    for (var i = 0; i < genericType.GenericArguments.Count; ++i)
+                    {
+                        var argument = genericType.GenericArguments[i];
+
+                        if (genericParameters != null && genericParameters.ContainsKey(argument.Name))
+                        {
+                            newGenericType.GenericArguments.Add(genericParameters[argument.Name]);
+                        }
+                        else
+                        {
+                            newGenericType.GenericArguments.Add(argument);
+                        }
+                    }
+                    fieldTypes.Add(newGenericType);
+                }
+                else
+                {
+                    fieldTypes.Add(field.FieldType);
+                }
+            }
+
+            if (type.BaseType == null || type.BaseType.Name == nameof(NetworkBehaviour))
+            {
+                return;
+            }
+            var genericParams = new Dictionary<string, TypeReference>();
+            var resolved = type.BaseType.Resolve();
+            if (type.BaseType.IsGenericInstance)
+            {
+                var genericType = (GenericInstanceType)type.BaseType;
+                for (var i = 0; i < genericType.GenericArguments.Count; ++i)
+                {
+                    genericParams[resolved.GenericParameters[i].Name] = genericType.GenericArguments[i];
+                }
+            }
+            GetAllFieldsAndResolveGenerics(resolved, ref fieldTypes, genericParams);
+        }
+
         private void ProcessNetworkBehaviour(TypeDefinition typeDefinition, string[] assemblyDefines)
         {
             var rpcHandlers = new List<(uint RpcMethodId, MethodDefinition RpcHandler)>();
@@ -416,6 +746,28 @@ namespace Unity.Netcode.Editor.CodeGen
                 }
             }
 
+            if (!typeDefinition.HasGenericParameters && !typeDefinition.IsGenericInstance)
+            {
+                var fieldTypes = new List<TypeReference>();
+                GetAllFieldsAndResolveGenerics(typeDefinition, ref fieldTypes);
+                foreach (var type in fieldTypes)
+                {
+                    //var type = field.FieldType;
+                    if (type.IsGenericInstance)
+                    {
+                        if (type.Resolve().Name == typeof(NetworkVariable<>).Name || type.Resolve().Name == typeof(NetworkList<>).Name)
+                        {
+                            var genericInstanceType = (GenericInstanceType)type;
+                            var wrappedType = genericInstanceType.GenericArguments[0];
+                            if (!m_WrappedNetworkVariableTypes.Contains(wrappedType))
+                            {
+                                m_WrappedNetworkVariableTypes.Add(wrappedType);
+                            }
+                        }
+                    }
+                }
+            }
+
             if (rpcHandlers.Count > 0 || rpcNames.Count > 0)
             {
                 var staticCtorMethodDef = typeDefinition.GetStaticConstructor();
@@ -669,7 +1021,7 @@ namespace Unity.Netcode.Editor.CodeGen
                     {
                         if (parameters[1].IsIn)
                         {
-                            if (parameters[1].ParameterType.Resolve() == paramType.MakeByReferenceType().Resolve() &&
+                            if (((ByReferenceType)parameters[1].ParameterType).ElementType.FullName == paramType.FullName &&
                                 ((ByReferenceType)parameters[1].ParameterType).ElementType.IsArray == paramType.IsArray)
                             {
                                 methodRef = method;
@@ -679,8 +1031,7 @@ namespace Unity.Netcode.Editor.CodeGen
                         }
                         else
                         {
-
-                            if (parameters[1].ParameterType.Resolve() == paramType.Resolve() &&
+                            if (parameters[1].ParameterType.FullName == paramType.FullName &&
                                 parameters[1].ParameterType.IsArray == paramType.IsArray)
                             {
                                 methodRef = method;
@@ -813,7 +1164,7 @@ namespace Unity.Netcode.Editor.CodeGen
                     var parameters = method.Resolve().Parameters;
                     if (method.Name == k_ReadValueMethodName &&
                         parameters[1].IsOut &&
-                        parameters[1].ParameterType.Resolve() == paramType.MakeByReferenceType().Resolve() &&
+                        ((ByReferenceType)parameters[1].ParameterType).ElementType.FullName == paramType.FullName &&
                         ((ByReferenceType)parameters[1].ParameterType).ElementType.IsArray == paramType.IsArray)
                     {
                         methodRef = method;

Editor/HiddenScriptEditor.cs

@@ -0,0 +1,81 @@
+using Unity.Netcode.Components;
+#if UNITY_UNET_PRESENT
+using Unity.Netcode.Transports.UNET;
+#endif
+using Unity.Netcode.Transports.UTP;
+using UnityEditor;
+
+namespace Unity.Netcode.Editor
+{
+    /// <summary>
+    /// Internal use. Hides the script field for the given component.
+    /// </summary>
+    public class HiddenScriptEditor : UnityEditor.Editor
+    {
+        private static readonly string[] k_HiddenFields = { "m_Script" };
+
+        /// <summary>
+        /// Draws inspector properties without the script field.
+        /// </summary>
+        public override void OnInspectorGUI()
+        {
+            EditorGUI.BeginChangeCheck();
+            serializedObject.UpdateIfRequiredOrScript();
+            DrawPropertiesExcluding(serializedObject, k_HiddenFields);
+            serializedObject.ApplyModifiedProperties();
+            EditorGUI.EndChangeCheck();
+        }
+    }
+#if UNITY_UNET_PRESENT
+    /// <summary>
+    /// Internal use. Hides the script field for UNetTransport.
+    /// </summary>
+    [CustomEditor(typeof(UNetTransport), true)]
+    public class UNetTransportEditor : HiddenScriptEditor
+    {
+
+    }
+#endif
+
+    /// <summary>
+    /// Internal use. Hides the script field for UnityTransport.
+    /// </summary>
+    [CustomEditor(typeof(UnityTransport), true)]
+    public class UnityTransportEditor : HiddenScriptEditor
+    {
+
+    }
+
+#if COM_UNITY_MODULES_ANIMATION
+    /// <summary>
+    /// Internal use. Hides the script field for NetworkAnimator.
+    /// </summary>
+    [CustomEditor(typeof(NetworkAnimator), true)]
+    public class NetworkAnimatorEditor : HiddenScriptEditor
+    {
+
+    }
+#endif
+
+#if COM_UNITY_MODULES_PHYSICS
+    /// <summary>
+    /// Internal use. Hides the script field for NetworkRigidbody.
+    /// </summary>
+    [CustomEditor(typeof(NetworkRigidbody), true)]
+    public class NetworkRigidbodyEditor : HiddenScriptEditor
+    {
+
+    }
+#endif
+
+#if COM_UNITY_MODULES_PHYSICS2D
+    /// <summary>
+    /// Internal use. Hides the script field for NetworkRigidbody2D.
+    /// </summary>
+    [CustomEditor(typeof(NetworkRigidbody2D), true)]
+    public class NetworkRigidbody2DEditor : HiddenScriptEditor
+    {
+
+    }
+#endif
+}

Editor/HiddenScriptEditor.cs.meta

@@ -0,0 +1,3 @@
+fileFormatVersion: 2
+guid: ebf622cc80e94f488e59caf8b7419f50
+timeCreated: 1661959406

Editor/NetworkBehaviourEditor.cs

@@ -263,8 +263,7 @@ namespace Unity.Netcode.Editor
 
             // Now get the root parent transform to the current GameObject (or itself)
             var rootTransform = GetRootParentTransform(gameObject.transform);
-            var networkManager = rootTransform.GetComponent<NetworkManager>();
-            if (networkManager == null)
+            if (!rootTransform.TryGetComponent<NetworkManager>(out var networkManager))
             {
                 networkManager = rootTransform.GetComponentInChildren<NetworkManager>();
             }
@@ -299,8 +298,7 @@ namespace Unity.Netcode.Editor
 
             // Otherwise, check to see if there is any NetworkObject from the root GameObject down to all children.
             // If not, notify the user that NetworkBehaviours require that the relative GameObject has a NetworkObject component.
-            var networkObject = rootTransform.GetComponent<NetworkObject>();
-            if (networkObject == null)
+            if (!rootTransform.TryGetComponent<NetworkObject>(out var networkObject))
             {
                 networkObject = rootTransform.GetComponentInChildren<NetworkObject>();
 

Editor/NetworkManagerEditor.cs

@@ -214,18 +214,6 @@ namespace Unity.Netcode.Editor
             DrawInstallMultiplayerToolsTip();
 #endif
 
-            {
-                var iterator = serializedObject.GetIterator();
-
-                for (bool enterChildren = true; iterator.NextVisible(enterChildren); enterChildren = false)
-                {
-                    using (new EditorGUI.DisabledScope("m_Script" == iterator.propertyPath))
-                    {
-                        EditorGUILayout.PropertyField(iterator, false);
-                    }
-                }
-            }
-
             if (!m_NetworkManager.IsServer && !m_NetworkManager.IsClient)
             {
                 serializedObject.Update();

Editor/NetworkManagerHelper.cs

@@ -64,7 +64,7 @@ namespace Unity.Netcode.Editor
         {
             var scenesList = EditorBuildSettings.scenes.ToList();
             var activeScene = SceneManager.GetActiveScene();
-            var isSceneInBuildSettings = scenesList.Where((c) => c.path == activeScene.path).Count() == 1;
+            var isSceneInBuildSettings = scenesList.Count((c) => c.path == activeScene.path) == 1;
             var networkManager = Object.FindObjectOfType<NetworkManager>();
             if (!isSceneInBuildSettings && networkManager != null)
             {
@@ -109,9 +109,8 @@ namespace Unity.Netcode.Editor
         public void CheckAndNotifyUserNetworkObjectRemoved(NetworkManager networkManager, bool editorTest = false)
         {
             // Check for any NetworkObject at the same gameObject relative layer
-            var networkObject = networkManager.gameObject.GetComponent<NetworkObject>();
 
-            if (networkObject == null)
+            if (!networkManager.gameObject.TryGetComponent<NetworkObject>(out var networkObject))
             {
                 // if none is found, check to see if any children have a NetworkObject
                 networkObject = networkManager.gameObject.GetComponentInChildren<NetworkObject>();

Editor/NetworkObjectEditor.cs

@@ -15,6 +15,8 @@ namespace Unity.Netcode.Editor
         private NetworkObject m_NetworkObject;
         private bool m_ShowObservers;
 
+        private static readonly string[] k_HiddenFields = { "m_Script" };
+
         private void Initialize()
         {
             if (m_Initialized)
@@ -95,7 +97,11 @@ namespace Unity.Netcode.Editor
             }
             else
             {
-                base.OnInspectorGUI();
+                EditorGUI.BeginChangeCheck();
+                serializedObject.UpdateIfRequiredOrScript();
+                DrawPropertiesExcluding(serializedObject, k_HiddenFields);
+                serializedObject.ApplyModifiedProperties();
+                EditorGUI.EndChangeCheck();
 
                 var guiEnabled = GUI.enabled;
                 GUI.enabled = false;

Editor/com.unity.netcode.editor.asmdef

@@ -13,6 +13,26 @@
             "name": "com.unity.multiplayer.tools",
             "expression": "",
             "define": "MULTIPLAYER_TOOLS"
+        },
+        {
+            "name": "Unity",
+            "expression": "(0,2022.2.0a5)",
+            "define": "UNITY_UNET_PRESENT"
+        },
+        {
+            "name": "com.unity.modules.animation",
+            "expression": "",
+            "define": "COM_UNITY_MODULES_ANIMATION"
+        },
+        {
+            "name": "com.unity.modules.physics",
+            "expression": "",
+            "define": "COM_UNITY_MODULES_PHYSICS"
+        },
+        {
+            "name": "com.unity.modules.physics2d",
+            "expression": "",
+            "define": "COM_UNITY_MODULES_PHYSICS2D"
         }
     ]
-}
+}

README.md

@@ -9,7 +9,7 @@ Netcode for GameObjects is a Unity package that provides networking capabilities
 
 Visit the [Multiplayer Docs Site](https://docs-multiplayer.unity3d.com/) for package & API documentation, as well as information about several samples which leverage the Netcode for GameObjects package.
 
-You can also jump right into our [Hello World](https://docs-multiplayer.unity3d.com/netcode/current/tutorials/helloworld/helloworldintro) guide for a taste of how to use the framework for basic networked tasks.
+You can also jump right into our [Hello World](https://docs-multiplayer.unity3d.com/netcode/current/tutorials/helloworld) guide for a taste of how to use the framework for basic networked tasks.
 
 ### Community and Feedback
 

Runtime/AssemblyInfo.cs

@@ -12,3 +12,4 @@ using System.Runtime.CompilerServices;
 [assembly: InternalsVisibleTo("Unity.Netcode.RuntimeTests")]
 [assembly: InternalsVisibleTo("Unity.Netcode.TestHelpers.Runtime")]
 [assembly: InternalsVisibleTo("Unity.Netcode.Adapter.UTP")]
+[assembly: InternalsVisibleTo("Unity.Multiplayer.Tools.Adapters.Ngo1WithUtp2")]

Runtime/Core/NetworkBehaviour.cs

@@ -235,14 +235,42 @@ namespace Unity.Netcode
 #if DEVELOPMENT_BUILD || UNITY_EDITOR
             if (NetworkManager.__rpc_name_table.TryGetValue(rpcMethodId, out var rpcMethodName))
             {
-                foreach (var client in NetworkManager.ConnectedClients)
+                if (clientRpcParams.Send.TargetClientIds != null)
                 {
-                    NetworkManager.NetworkMetrics.TrackRpcSent(
-                        client.Key,
-                        NetworkObject,
-                        rpcMethodName,
-                        __getTypeName(),
-                        rpcWriteSize);
+                    foreach (var targetClientId in clientRpcParams.Send.TargetClientIds)
+                    {
+                        NetworkManager.NetworkMetrics.TrackRpcSent(
+                            targetClientId,
+                            NetworkObject,
+                            rpcMethodName,
+                            __getTypeName(),
+                            rpcWriteSize);
+                    }
+                }
+                else if (clientRpcParams.Send.TargetClientIdsNativeArray != null)
+                {
+                    foreach (var targetClientId in clientRpcParams.Send.TargetClientIdsNativeArray)
+                    {
+                        NetworkManager.NetworkMetrics.TrackRpcSent(
+                            targetClientId,
+                            NetworkObject,
+                            rpcMethodName,
+                            __getTypeName(),
+                            rpcWriteSize);
+                    }
+                }
+                else
+                {
+                    var observerEnumerator = NetworkObject.Observers.GetEnumerator();
+                    while (observerEnumerator.MoveNext())
+                    {
+                        NetworkManager.NetworkMetrics.TrackRpcSent(
+                            observerEnumerator.Current,
+                            NetworkObject,
+                            rpcMethodName,
+                            __getTypeName(),
+                            rpcWriteSize);
+                    }
                 }
             }
 #endif
@@ -331,7 +359,8 @@ namespace Unity.Netcode
                 // in Update and/or in FixedUpdate could still be checking NetworkBehaviour.NetworkObject directly (i.e. does it exist?)
                 // or NetworkBehaviour.IsSpawned (i.e. to early exit if not spawned) which, in turn, could generate several Warning messages
                 // per spawned NetworkObject.  Checking for ShutdownInProgress prevents these unnecessary LogWarning messages.
-                if (m_NetworkObject == null && (NetworkManager.Singleton == null || !NetworkManager.Singleton.ShutdownInProgress))
+                // We must check IsSpawned, otherwise a warning will be logged under certain valid conditions (see OnDestroy)
+                if (IsSpawned && m_NetworkObject == null && (NetworkManager.Singleton == null || !NetworkManager.Singleton.ShutdownInProgress))
                 {
                     if (NetworkLog.CurrentLogLevel <= LogLevel.Normal)
                     {
@@ -435,14 +464,41 @@ namespace Unity.Netcode
             IsSpawned = true;
             InitializeVariables();
             UpdateNetworkProperties();
-            OnNetworkSpawn();
+        }
+
+        internal void VisibleOnNetworkSpawn()
+        {
+            try
+            {
+                OnNetworkSpawn();
+            }
+            catch (Exception e)
+            {
+                Debug.LogException(e);
+            }
+
+            InitializeVariables();
+            if (IsServer)
+            {
+                // Since we just spawned the object and since user code might have modified their NetworkVariable, esp.
+                // NetworkList, we need to mark the object as free of updates.
+                // This should happen for all objects on the machine triggering the spawn.
+                PostNetworkVariableWrite(true);
+            }
         }
 
         internal void InternalOnNetworkDespawn()
         {
             IsSpawned = false;
             UpdateNetworkProperties();
-            OnNetworkDespawn();
+            try
+            {
+                OnNetworkDespawn();
+            }
+            catch (Exception e)
+            {
+                Debug.LogException(e);
+            }
         }
 
         /// <summary>
@@ -575,16 +631,30 @@ namespace Unity.Netcode
             NetworkVariableIndexesToResetSet.Clear();
         }
 
-        internal void PostNetworkVariableWrite()
+        internal void PostNetworkVariableWrite(bool forced = false)
         {
-            // mark any variables we wrote as no longer dirty
-            for (int i = 0; i < NetworkVariableIndexesToReset.Count; i++)
+            if (forced)
             {
-                NetworkVariableFields[NetworkVariableIndexesToReset[i]].ResetDirty();
+                // Mark every variable as no longer dirty. We just spawned the object and whatever the game code did
+                // during OnNetworkSpawn has been sent and needs to be cleared
+                for (int i = 0; i < NetworkVariableFields.Count; i++)
+                {
+                    NetworkVariableFields[i].ResetDirty();
+                }
             }
+            else
+            {
+                // mark any variables we wrote as no longer dirty
+                for (int i = 0; i < NetworkVariableIndexesToReset.Count; i++)
+                {
+                    NetworkVariableFields[NetworkVariableIndexesToReset[i]].ResetDirty();
+                }
+            }
+
+            MarkVariablesDirty(false);
         }
 
-        internal void VariableUpdate(ulong targetClientId)
+        internal void PreVariableUpdate()
         {
             if (!m_VarInit)
             {
@@ -592,6 +662,10 @@ namespace Unity.Netcode
             }
 
             PreNetworkVariableWrite();
+        }
+
+        internal void VariableUpdate(ulong targetClientId)
+        {
             NetworkVariableUpdate(targetClientId, NetworkBehaviourId);
         }
 
@@ -663,11 +737,11 @@ namespace Unity.Netcode
             return false;
         }
 
-        internal void MarkVariablesDirty()
+        internal void MarkVariablesDirty(bool dirty)
         {
             for (int j = 0; j < NetworkVariableFields.Count; j++)
             {
-                NetworkVariableFields[j].SetDirty(true);
+                NetworkVariableFields[j].SetDirty(dirty);
             }
         }
 
@@ -759,6 +833,14 @@ namespace Unity.Netcode
         /// </summary>
         public virtual void OnDestroy()
         {
+            if (NetworkObject != null && NetworkObject.IsSpawned && IsSpawned)
+            {
+                // If the associated NetworkObject is still spawned then this
+                // NetworkBehaviour will be removed from the NetworkObject's
+                // ChildNetworkBehaviours list.
+                NetworkObject.OnNetworkBehaviourDestroyed(this);
+            }
+
             // this seems odd to do here, but in fact especially in tests we can find ourselves
             //  here without having called InitializedVariables, which causes problems if any
             //  of those variables use native containers (e.g. NetworkList) as they won't be
@@ -770,6 +852,7 @@ namespace Unity.Netcode
                 InitializeVariables();
             }
 
+
             for (int i = 0; i < NetworkVariableFields.Count; i++)
             {
                 NetworkVariableFields[i].Dispose();

Runtime/Core/NetworkBehaviourUpdater.cs

@@ -8,12 +8,17 @@ namespace Unity.Netcode
     /// </summary>
     public class NetworkBehaviourUpdater
     {
-        private HashSet<NetworkObject> m_Touched = new HashSet<NetworkObject>();
+        private HashSet<NetworkObject> m_DirtyNetworkObjects = new HashSet<NetworkObject>();
 
 #if DEVELOPMENT_BUILD || UNITY_EDITOR
         private ProfilerMarker m_NetworkBehaviourUpdate = new ProfilerMarker($"{nameof(NetworkBehaviour)}.{nameof(NetworkBehaviourUpdate)}");
 #endif
 
+        internal void AddForUpdate(NetworkObject networkObject)
+        {
+            m_DirtyNetworkObjects.Add(networkObject);
+        }
+
         internal void NetworkBehaviourUpdate(NetworkManager networkManager)
         {
 #if DEVELOPMENT_BUILD || UNITY_EDITOR
@@ -21,59 +26,58 @@ namespace Unity.Netcode
 #endif
             try
             {
+                // NetworkObject references can become null, when hidden or despawned. Once NUll, there is no point
+                // trying to process them, even if they were previously marked as dirty.
+                m_DirtyNetworkObjects.RemoveWhere((sobj) => sobj == null);
+
                 if (networkManager.IsServer)
                 {
-                    m_Touched.Clear();
-                    for (int i = 0; i < networkManager.ConnectedClientsList.Count; i++)
+                    foreach (var dirtyObj in m_DirtyNetworkObjects)
                     {
-                        var client = networkManager.ConnectedClientsList[i];
-                        var spawnedObjs = networkManager.SpawnManager.SpawnedObjectsList;
-                        m_Touched.UnionWith(spawnedObjs);
-                        foreach (var sobj in spawnedObjs)
+                        for (int k = 0; k < dirtyObj.ChildNetworkBehaviours.Count; k++)
                         {
-                            if (sobj.IsNetworkVisibleTo(client.ClientId))
+                            dirtyObj.ChildNetworkBehaviours[k].PreVariableUpdate();
+                        }
+
+                        for (int i = 0; i < networkManager.ConnectedClientsList.Count; i++)
+                        {
+                            var client = networkManager.ConnectedClientsList[i];
+
+                            if (dirtyObj.IsNetworkVisibleTo(client.ClientId))
                             {
                                 // Sync just the variables for just the objects this client sees
-                                for (int k = 0; k < sobj.ChildNetworkBehaviours.Count; k++)
+                                for (int k = 0; k < dirtyObj.ChildNetworkBehaviours.Count; k++)
                                 {
-                                    sobj.ChildNetworkBehaviours[k].VariableUpdate(client.ClientId);
+                                    dirtyObj.ChildNetworkBehaviours[k].VariableUpdate(client.ClientId);
                                 }
                             }
                         }
                     }
-
-                    // Now, reset all the no-longer-dirty variables
-                    foreach (var sobj in m_Touched)
-                    {
-                        for (int k = 0; k < sobj.ChildNetworkBehaviours.Count; k++)
-                        {
-                            sobj.ChildNetworkBehaviours[k].PostNetworkVariableWrite();
-                        }
-                    }
                 }
                 else
                 {
                     // when client updates the server, it tells it about all its objects
-                    foreach (var sobj in networkManager.SpawnManager.SpawnedObjectsList)
+                    foreach (var sobj in m_DirtyNetworkObjects)
                     {
                         if (sobj.IsOwner)
                         {
+                            for (int k = 0; k < sobj.ChildNetworkBehaviours.Count; k++)
+                            {
+                                sobj.ChildNetworkBehaviours[k].PreVariableUpdate();
+                            }
                             for (int k = 0; k < sobj.ChildNetworkBehaviours.Count; k++)
                             {
                                 sobj.ChildNetworkBehaviours[k].VariableUpdate(NetworkManager.ServerClientId);
                             }
                         }
                     }
-
-                    // Now, reset all the no-longer-dirty variables
-                    foreach (var sobj in networkManager.SpawnManager.SpawnedObjectsList)
-                    {
-                        for (int k = 0; k < sobj.ChildNetworkBehaviours.Count; k++)
-                        {
-                            sobj.ChildNetworkBehaviours[k].PostNetworkVariableWrite();
-                        }
-                    }
                 }
+                // Now, reset all the no-longer-dirty variables
+                foreach (var dirtyobj in m_DirtyNetworkObjects)
+                {
+                    dirtyobj.PostNetworkVariableWrite();
+                }
+                m_DirtyNetworkObjects.Clear();
             }
             finally
             {

Runtime/Core/NetworkManager.cs

@@ -20,7 +20,7 @@ namespace Unity.Netcode
     /// <summary>
     /// The main component of the library
     /// </summary>
-    [AddComponentMenu("Netcode/" + nameof(NetworkManager), -100)]
+    [AddComponentMenu("Netcode/Network Manager", -100)]
     public class NetworkManager : MonoBehaviour, INetworkUpdateSystem
     {
 #pragma warning disable IDE1006 // disable naming rule violation check
@@ -51,10 +51,15 @@ namespace Unity.Netcode
 
         internal static string PrefabDebugHelper(NetworkPrefab networkPrefab)
         {
-            return $"{nameof(NetworkPrefab)} \"{networkPrefab.Prefab.gameObject.name}\"";
+            return $"{nameof(NetworkPrefab)} \"{networkPrefab.Prefab.name}\"";
         }
 
-        internal NetworkBehaviourUpdater BehaviourUpdater { get; private set; }
+        internal NetworkBehaviourUpdater BehaviourUpdater { get; set; }
+
+        internal void MarkNetworkObjectDirty(NetworkObject networkObject)
+        {
+            BehaviourUpdater.AddForUpdate(networkObject);
+        }
 
         internal MessagingSystem MessagingSystem { get; private set; }
 
@@ -182,8 +187,7 @@ namespace Unity.Netcode
         /// <returns>a <see cref="GameObject"/> that is either the override or if no overrides exist it returns the same as the one passed in as a parameter</returns>
         public GameObject GetNetworkPrefabOverride(GameObject gameObject)
         {
-            var networkObject = gameObject.GetComponent<NetworkObject>();
-            if (networkObject != null)
+            if (gameObject.TryGetComponent<NetworkObject>(out var networkObject))
             {
                 if (NetworkConfig.NetworkPrefabOverrideLinks.ContainsKey(networkObject.GlobalObjectIdHash))
                 {
@@ -362,10 +366,22 @@ namespace Unity.Netcode
         public bool IsListening { get; internal set; }
 
         /// <summary>
-        /// Gets if we are connected as a client
+        /// When true, the client is connected, approved, and synchronized with
+        /// the server.
         /// </summary>
         public bool IsConnectedClient { get; internal set; }
 
+        /// <summary>
+        /// Is true when the client has been approved.
+        /// </summary>
+        /// <remarks>
+        /// This only reflects the client's approved status and does not mean the client
+        /// has finished the connection and synchronization process. The server-host will
+        /// always be approved upon being starting the <see cref="NetworkManager"/>
+        /// <see cref="IsConnectedClient"/>
+        /// </remarks>
+        public bool IsApproved { get; internal set; }
+
         /// <summary>
         /// Can be used to determine if the <see cref="NetworkManager"/> is currently shutting itself down
         /// </summary>
@@ -514,8 +530,7 @@ namespace Unity.Netcode
                 var networkPrefabGo = networkPrefab?.Prefab;
                 if (networkPrefabGo != null)
                 {
-                    var networkObject = networkPrefabGo.GetComponent<NetworkObject>();
-                    if (networkObject == null)
+                    if (!networkPrefabGo.TryGetComponent<NetworkObject>(out var networkObject))
                     {
                         if (NetworkLog.CurrentLogLevel <= LogLevel.Normal)
                         {
@@ -690,8 +705,7 @@ namespace Unity.Netcode
             }
             else if (networkPrefab.Override == NetworkPrefabOverride.None)
             {
-                networkObject = networkPrefab.Prefab.GetComponent<NetworkObject>();
-                if (networkObject == null)
+                if (!networkPrefab.Prefab.TryGetComponent(out networkObject))
                 {
                     if (NetworkLog.CurrentLogLevel <= LogLevel.Error)
                     {
@@ -737,8 +751,7 @@ namespace Unity.Netcode
                             }
                             else
                             {
-                                networkObject = networkPrefab.SourcePrefabToOverride.GetComponent<NetworkObject>();
-                                if (networkObject == null)
+                                if (!networkPrefab.SourcePrefabToOverride.TryGetComponent(out networkObject))
                                 {
                                     if (NetworkLog.CurrentLogLevel <= LogLevel.Error)
                                     {
@@ -876,6 +889,8 @@ namespace Unity.Netcode
                 return;
             }
 
+            IsApproved = false;
+
             ComponentFactory.SetDefaults();
 
             if (NetworkLog.CurrentLogLevel <= LogLevel.Developer)
@@ -963,8 +978,7 @@ namespace Unity.Netcode
             // If we have a player prefab, then we need to verify it is in the list of NetworkPrefabOverrideLinks for client side spawning.
             if (NetworkConfig.PlayerPrefab != null)
             {
-                var playerPrefabNetworkObject = NetworkConfig.PlayerPrefab.GetComponent<NetworkObject>();
-                if (playerPrefabNetworkObject != null)
+                if (NetworkConfig.PlayerPrefab.TryGetComponent<NetworkObject>(out var playerPrefabNetworkObject))
                 {
                     //In the event there is no NetworkPrefab entry (i.e. no override for default player prefab)
                     if (!NetworkConfig.NetworkPrefabOverrideLinks.ContainsKey(playerPrefabNetworkObject
@@ -1018,24 +1032,38 @@ namespace Unity.Netcode
             }
 
             Initialize(true);
+            IsServer = true;
+            IsClient = false;
+            IsListening = true;
 
-            // If we failed to start then shutdown and notify user that the transport failed to start
-            if (NetworkConfig.NetworkTransport.StartServer())
+            try
             {
-                IsServer = true;
-                IsClient = false;
-                IsListening = true;
+                // If we failed to start then shutdown and notify user that the transport failed to start
+                if (NetworkConfig.NetworkTransport.StartServer())
+                {
+                    SpawnManager.ServerSpawnSceneObjectsOnStartSweep();
 
-                SpawnManager.ServerSpawnSceneObjectsOnStartSweep();
+                    OnServerStarted?.Invoke();
+                    IsApproved = true;
+                    return true;
+                }
+                else
+                {
+                    IsServer = false;
+                    IsClient = false;
+                    IsListening = false;
 
-                OnServerStarted?.Invoke();
-                return true;
+                    Debug.LogError($"Server is shutting down due to network transport start failure of {NetworkConfig.NetworkTransport.GetType().Name}!");
+                    OnTransportFailure?.Invoke();
+                    Shutdown();
+                }
             }
-            else
+            catch (Exception)
             {
-                Debug.LogError($"Server is shutting down due to network transport start failure of {NetworkConfig.NetworkTransport.GetType().Name}!");
-                OnTransportFailure?.Invoke();
-                Shutdown();
+                IsServer = false;
+                IsClient = false;
+                IsListening = false;
+                throw;
             }
 
             return false;
@@ -1093,23 +1121,38 @@ namespace Unity.Netcode
 
             Initialize(true);
 
-            // If we failed to start then shutdown and notify user that the transport failed to start
-            if (!NetworkConfig.NetworkTransport.StartServer())
+            IsServer = true;
+            IsClient = true;
+            IsListening = true;
+
+            try
             {
-                Debug.LogError($"Server is shutting down due to network transport start failure of {NetworkConfig.NetworkTransport.GetType().Name}!");
-                OnTransportFailure?.Invoke();
-                Shutdown();
-                return false;
+                // If we failed to start then shutdown and notify user that the transport failed to start
+                if (!NetworkConfig.NetworkTransport.StartServer())
+                {
+                    Debug.LogError($"Server is shutting down due to network transport start failure of {NetworkConfig.NetworkTransport.GetType().Name}!");
+                    OnTransportFailure?.Invoke();
+                    Shutdown();
+
+                    IsServer = false;
+                    IsClient = false;
+                    IsListening = false;
+
+                    return false;
+                }
+            }
+            catch (Exception)
+            {
+                IsServer = false;
+                IsClient = false;
+                IsListening = false;
+                throw;
             }
 
             MessagingSystem.ClientConnected(ServerClientId);
             LocalClientId = ServerClientId;
             NetworkMetrics.SetConnectionId(LocalClientId);
 
-            IsServer = true;
-            IsClient = true;
-            IsListening = true;
-
             if (NetworkConfig.ConnectionApproval && ConnectionApprovalCallback != null)
             {
                 var response = new ConnectionApprovalResponse();
@@ -1123,6 +1166,7 @@ namespace Unity.Netcode
                 }
 
                 response.Approved = true;
+                IsApproved = true;
                 HandleConnectionApproval(ServerClientId, response);
             }
             else
@@ -1384,6 +1428,20 @@ namespace Unity.Netcode
             }
 
             IsConnectedClient = false;
+            IsApproved = false;
+
+            // We need to clean up NetworkObjects before we reset the IsServer
+            // and IsClient properties. This provides consistency of these two
+            // property values for NetworkObjects that are still spawned when
+            // the shutdown cycle begins.
+            if (SpawnManager != null)
+            {
+                SpawnManager.DespawnAndDestroyNetworkObjects();
+                SpawnManager.ServerResetShudownStateForSceneObjects();
+
+                SpawnManager = null;
+            }
+
             IsServer = false;
             IsClient = false;
 
@@ -1406,14 +1464,6 @@ namespace Unity.Netcode
                 NetworkConfig.NetworkTransport.OnTransportEvent -= HandleRawTransportPoll;
             }
 
-            if (SpawnManager != null)
-            {
-                SpawnManager.DespawnAndDestroyNetworkObjects();
-                SpawnManager.ServerResetShudownStateForSceneObjects();
-
-                SpawnManager = null;
-            }
-
             if (DeferredMessageManager != null)
             {
                 DeferredMessageManager.CleanupAllTriggers();
@@ -1550,7 +1600,7 @@ namespace Unity.Netcode
             }
 
             // Only update RTT here, server time is updated by time sync messages
-            var reset = NetworkTimeSystem.Advance(Time.deltaTime);
+            var reset = NetworkTimeSystem.Advance(Time.unscaledDeltaTime);
             if (reset)
             {
                 NetworkTickSystem.Reset(NetworkTimeSystem.LocalTime, NetworkTimeSystem.ServerTime);
@@ -1559,7 +1609,7 @@ namespace Unity.Netcode
 
             if (IsServer == false)
             {
-                NetworkTimeSystem.Sync(NetworkTimeSystem.LastSyncedServerTimeSec + Time.deltaTime, NetworkConfig.NetworkTransport.GetCurrentRtt(ServerClientId) / 1000d);
+                NetworkTimeSystem.Sync(NetworkTimeSystem.LastSyncedServerTimeSec + Time.unscaledDeltaTime, NetworkConfig.NetworkTransport.GetCurrentRtt(ServerClientId) / 1000d);
             }
         }
 
@@ -1604,7 +1654,9 @@ namespace Unity.Netcode
         {
             var message = new ConnectionRequestMessage
             {
-                ConfigHash = NetworkConfig.GetConfig(),
+                // Since only a remote client will send a connection request,
+                // we should always force the rebuilding of the NetworkConfig hash value
+                ConfigHash = NetworkConfig.GetConfig(false),
                 ShouldSendConnectionData = NetworkConfig.ConnectionApproval,
                 ConnectionData = NetworkConfig.ConnectionData
             };
@@ -1613,23 +1665,73 @@ namespace Unity.Netcode
 
         private IEnumerator ApprovalTimeout(ulong clientId)
         {
-            NetworkTime timeStarted = LocalTime;
+            var timeStarted = IsServer ? LocalTime.TimeAsFloat : Time.realtimeSinceStartup;
+            var timedOut = false;
+            var connectionApproved = false;
+            var connectionNotApproved = false;
+            var timeoutMarker = timeStarted + NetworkConfig.ClientConnectionBufferTimeout;
 
-            //We yield every frame incase a pending client disconnects and someone else gets its connection id
-            while ((LocalTime - timeStarted).Time < NetworkConfig.ClientConnectionBufferTimeout && PendingClients.ContainsKey(clientId))
+            while (IsListening && !ShutdownInProgress && !timedOut && !connectionApproved)
             {
                 yield return null;
+                // Check if we timed out
+                timedOut = timeoutMarker < (IsServer ? LocalTime.TimeAsFloat : Time.realtimeSinceStartup);
+
+                if (IsServer)
+                {
+                    // When the client is no longer in the pending clients list and is in the connected clients list
+                    // it has been approved
+                    connectionApproved = !PendingClients.ContainsKey(clientId) && ConnectedClients.ContainsKey(clientId);
+
+                    // For the server side, if the client is in neither list then it was declined or the client disconnected
+                    connectionNotApproved = !PendingClients.ContainsKey(clientId) && !ConnectedClients.ContainsKey(clientId);
+                }
+                else
+                {
+                    connectionApproved = IsApproved;
+                }
             }
 
-            if (PendingClients.ContainsKey(clientId) && !ConnectedClients.ContainsKey(clientId))
+            // Exit coroutine if we are no longer listening or a shutdown is in progress (client or server)
+            if (!IsListening || ShutdownInProgress)
+            {
+                yield break;
+            }
+
+            // If the client timed out or was not approved
+            if (timedOut || connectionNotApproved)
             {
                 // Timeout
                 if (NetworkLog.CurrentLogLevel <= LogLevel.Developer)
                 {
-                    NetworkLog.LogInfo($"Client {clientId} Handshake Timed Out");
+                    if (timedOut)
+                    {
+                        if (IsServer)
+                        {
+                            // Log a warning that the transport detected a connection but then did not receive a follow up connection request message.
+                            // (hacking or something happened to the server's network connection)
+                            NetworkLog.LogWarning($"Server detected a transport connection from Client-{clientId}, but timed out waiting for the connection request message.");
+                        }
+                        else
+                        {
+                            // We only provide informational logging for the client side
+                            NetworkLog.LogInfo("Timed out waiting for the server to approve the connection request.");
+                        }
+                    }
+                    else if (connectionNotApproved)
+                    {
+                        NetworkLog.LogInfo($"Client-{clientId} was either denied approval or disconnected while being approved.");
+                    }
                 }
 
-                DisconnectClient(clientId);
+                if (IsServer)
+                {
+                    DisconnectClient(clientId);
+                }
+                else
+                {
+                    Shutdown(true);
+                }
             }
         }
 
@@ -1906,13 +2008,20 @@ namespace Unity.Netcode
                     var playerObject = networkClient.PlayerObject;
                     if (playerObject != null)
                     {
-                        if (PrefabHandler.ContainsHandler(ConnectedClients[clientId].PlayerObject.GlobalObjectIdHash))
+                        if (!playerObject.DontDestroyWithOwner)
                         {
-                            PrefabHandler.HandleNetworkPrefabDestroy(ConnectedClients[clientId].PlayerObject);
+                            if (PrefabHandler.ContainsHandler(ConnectedClients[clientId].PlayerObject.GlobalObjectIdHash))
+                            {
+                                PrefabHandler.HandleNetworkPrefabDestroy(ConnectedClients[clientId].PlayerObject);
+                            }
+                            else
+                            {
+                                Destroy(playerObject.gameObject);
+                            }
                         }
                         else
                         {
-                            Destroy(playerObject.gameObject);
+                            playerObject.RemoveOwnership();
                         }
                     }
 
@@ -2023,14 +2132,31 @@ namespace Unity.Netcode
 
                 if (response.CreatePlayerObject)
                 {
-                    var networkObject = SpawnManager.CreateLocalNetworkObject(
-                        isSceneObject: false,
-                        response.PlayerPrefabHash ?? NetworkConfig.PlayerPrefab.GetComponent<NetworkObject>().GlobalObjectIdHash,
-                        ownerClientId,
-                        parentNetworkId: null,
-                        networkSceneHandle: null,
-                        response.Position,
-                        response.Rotation);
+                    var playerPrefabHash = response.PlayerPrefabHash ?? NetworkConfig.PlayerPrefab.GetComponent<NetworkObject>().GlobalObjectIdHash;
+
+                    // Generate a SceneObject for the player object to spawn
+                    var sceneObject = new NetworkObject.SceneObject
+                    {
+                        Header = new NetworkObject.SceneObject.HeaderData
+                        {
+                            IsPlayerObject = true,
+                            OwnerClientId = ownerClientId,
+                            IsSceneObject = false,
+                            HasTransform = true,
+                            Hash = playerPrefabHash,
+                        },
+                        TargetClientId = ownerClientId,
+                        Transform = new NetworkObject.SceneObject.TransformData
+                        {
+                            Position = response.Position.GetValueOrDefault(),
+                            Rotation = response.Rotation.GetValueOrDefault()
+                        }
+                    };
+
+                    // Create the player NetworkObject locally
+                    var networkObject = SpawnManager.CreateLocalNetworkObject(sceneObject);
+
+                    // Spawn the player NetworkObject locally
                     SpawnManager.SpawnNetworkObjectLocally(
                         networkObject,
                         SpawnManager.GetNetworkObjectId(),
@@ -2060,6 +2186,20 @@ namespace Unity.Netcode
 
                     SendMessage(ref message, NetworkDelivery.ReliableFragmentedSequenced, ownerClientId);
 
+                    for (int index = 0; index < MessagingSystem.MessageHandlers.Length; index++)
+                    {
+                        if (MessagingSystem.MessageTypes[index] != null)
+                        {
+                            var orderingMessage = new OrderingMessage
+                            {
+                                Order = index,
+                                Hash = XXHash.Hash32(MessagingSystem.MessageTypes[index].FullName)
+                            };
+
+                            SendMessage(ref orderingMessage, NetworkDelivery.ReliableFragmentedSequenced, ownerClientId);
+                        }
+                    }
+
                     // If scene management is enabled, then let NetworkSceneManager handle the initial scene and NetworkObject synchronization
                     if (!NetworkConfig.EnableSceneManagement)
                     {

Runtime/Core/NetworkObject.cs

@@ -9,7 +9,7 @@ namespace Unity.Netcode
     /// <summary>
     /// A component used to identify that a GameObject in the network
     /// </summary>
-    [AddComponentMenu("Netcode/" + nameof(NetworkObject), -99)]
+    [AddComponentMenu("Netcode/Network Object", -99)]
     [DisallowMultipleComponent]
     public sealed class NetworkObject : MonoBehaviour
     {
@@ -129,7 +129,7 @@ namespace Unity.Netcode
 
         /// <summary>
         /// Whether or not to destroy this object if it's owner is destroyed.
-        /// If false, the objects ownership will be given to the server.
+        /// If true, the objects ownership will be given to the server.
         /// </summary>
         public bool DontDestroyWithOwner;
 
@@ -235,9 +235,19 @@ namespace Unity.Netcode
         }
 
         /// <summary>
-        /// Shows a previously hidden <see cref="NetworkObject"/> to a client
+        /// Makes the previously hidden <see cref="NetworkObject"/> "netcode visible" to the targeted client.
         /// </summary>
-        /// <param name="clientId">The client to show the <see cref="NetworkObject"/> to</param>
+        /// <remarks>
+        /// Usage: Use to start sending updates for a previously hidden <see cref="NetworkObject"/> to the targeted client.<br />
+        /// <br />
+        /// Dynamically Spawned: <see cref="NetworkObject"/>s will be instantiated and spawned on the targeted client side.<br />
+        /// In-Scene Placed: The instantiated but despawned <see cref="NetworkObject"/>s will be spawned on the targeted client side.<br />
+        /// <br />
+        /// See Also:<br />
+        /// <see cref="NetworkShow(ulong)"/><br />
+        /// <see cref="NetworkHide(ulong)"/> or <see cref="NetworkHide(List{NetworkObject}, ulong)"/><br />
+        /// </remarks>
+        /// <param name="clientId">The targeted client</param>
         public void NetworkShow(ulong clientId)
         {
             if (!IsSpawned)
@@ -260,11 +270,22 @@ namespace Unity.Netcode
             NetworkManager.SpawnManager.SendSpawnCallForObject(clientId, this);
         }
 
+
         /// <summary>
-        /// Shows a list of previously hidden <see cref="NetworkObject"/>s to a client
+        /// Makes a list of previously hidden <see cref="NetworkObject"/>s "netcode visible" for the client specified.
         /// </summary>
-        /// <param name="networkObjects">The <see cref="NetworkObject"/>s to show</param>
-        /// <param name="clientId">The client to show the objects to</param>
+        /// <remarks>
+        /// Usage: Use to start sending updates for previously hidden <see cref="NetworkObject"/>s to the targeted client.<br />
+        /// <br />
+        /// Dynamically Spawned: <see cref="NetworkObject"/>s will be instantiated and spawned on the targeted client's side.<br />
+        /// In-Scene Placed: Already instantiated but despawned <see cref="NetworkObject"/>s will be spawned on the targeted client's side.<br />
+        /// <br />
+        /// See Also:<br />
+        /// <see cref="NetworkShow(ulong)"/><br />
+        /// <see cref="NetworkHide(ulong)"/> or <see cref="NetworkHide(List{NetworkObject}, ulong)"/><br />
+        /// </remarks>
+        /// <param name="networkObjects">The objects to become "netcode visible" to the targeted client</param>
+        /// <param name="clientId">The targeted client</param>
         public static void NetworkShow(List<NetworkObject> networkObjects, ulong clientId)
         {
             if (networkObjects == null || networkObjects.Count == 0)
@@ -305,9 +326,19 @@ namespace Unity.Netcode
         }
 
         /// <summary>
-        /// Hides a object from a specific client
+        /// Hides the <see cref="NetworkObject"/> from the targeted client.
         /// </summary>
-        /// <param name="clientId">The client to hide the object for</param>
+        /// <remarks>
+        /// Usage: Use to stop sending updates to the targeted client, "netcode invisible", for a currently visible <see cref="NetworkObject"/>.<br />
+        /// <br />
+        /// Dynamically Spawned: <see cref="NetworkObject"/>s will be despawned and destroyed on the targeted client's side.<br />
+        /// In-Scene Placed: <see cref="NetworkObject"/>s will only be despawned on the targeted client's side.<br />
+        /// <br />
+        /// See Also:<br />
+        /// <see cref="NetworkHide(List{NetworkObject}, ulong)"/><br />
+        /// <see cref="NetworkShow(ulong)"/> or <see cref="NetworkShow(List{NetworkObject}, ulong)"/><br />
+        /// </remarks>
+        /// <param name="clientId">The targeted client</param>
         public void NetworkHide(ulong clientId)
         {
             if (!IsSpawned)
@@ -335,7 +366,7 @@ namespace Unity.Netcode
             var message = new DestroyObjectMessage
             {
                 NetworkObjectId = NetworkObjectId,
-                DestroyGameObject = true
+                DestroyGameObject = !IsSceneObject.Value
             };
             // Send destroy call
             var size = NetworkManager.SendMessage(ref message, NetworkDelivery.ReliableSequenced, clientId);
@@ -343,10 +374,20 @@ namespace Unity.Netcode
         }
 
         /// <summary>
-        /// Hides a list of objects from a client
+        /// Hides a list of <see cref="NetworkObject"/>s from the targeted client.
         /// </summary>
-        /// <param name="networkObjects">The objects to hide</param>
-        /// <param name="clientId">The client to hide the objects from</param>
+        /// <remarks>
+        /// Usage: Use to stop sending updates to the targeted client, "netcode invisible", for the currently visible <see cref="NetworkObject"/>s.<br />
+        /// <br />
+        /// Dynamically Spawned: <see cref="NetworkObject"/>s will be despawned and destroyed on the targeted client's side.<br />
+        /// In-Scene Placed: <see cref="NetworkObject"/>s will only be despawned on the targeted client's side.<br />
+        /// <br />
+        /// See Also:<br />
+        /// <see cref="NetworkHide(ulong)"/><br />
+        /// <see cref="NetworkShow(ulong)"/> or <see cref="NetworkShow(List{NetworkObject}, ulong)"/><br />
+        /// </remarks>
+        /// <param name="networkObjects">The <see cref="NetworkObject"/>s that will become "netcode invisible" to the targeted client</param>
+        /// <param name="clientId">The targeted client</param>
         public static void NetworkHide(List<NetworkObject> networkObjects, ulong clientId)
         {
             if (networkObjects == null || networkObjects.Count == 0)
@@ -394,7 +435,7 @@ namespace Unity.Netcode
         private void OnDestroy()
         {
             if (NetworkManager != null && NetworkManager.IsListening && NetworkManager.IsServer == false && IsSpawned &&
-                (IsSceneObject == null || (IsSceneObject != null && IsSceneObject.Value != true)))
+                (IsSceneObject == null || (IsSceneObject.Value != true)))
             {
                 throw new NotServerException($"Destroy a spawned {nameof(NetworkObject)} on a non-host client is not valid. Call {nameof(Destroy)} or {nameof(Despawn)} on the server/host instead.");
             }
@@ -455,8 +496,8 @@ namespace Unity.Netcode
         /// <summary>
         /// Spawns a <see cref="NetworkObject"/> across the network and makes it the player object for the given client
         /// </summary>
-        /// <param name="clientId">The clientId whos player object this is</param>
-        /// <param name="destroyWithScene">Should the object be destroyd when the scene is changed</param>
+        /// <param name="clientId">The clientId who's player object this is</param>
+        /// <param name="destroyWithScene">Should the object be destroyed when the scene is changed</param>
         public void SpawnAsPlayerObject(ulong clientId, bool destroyWithScene = false)
         {
             SpawnInternal(destroyWithScene, clientId, true);
@@ -468,6 +509,7 @@ namespace Unity.Netcode
         /// <param name="destroy">(true) the <see cref="GameObject"/> will be destroyed (false) the <see cref="GameObject"/> will persist after being despawned</param>
         public void Despawn(bool destroy = true)
         {
+            MarkVariablesDirty(false);
             NetworkManager.SpawnManager.DespawnObject(this, destroy);
         }
 
@@ -512,7 +554,14 @@ namespace Unity.Netcode
 
             for (int i = 0; i < ChildNetworkBehaviours.Count; i++)
             {
-                ChildNetworkBehaviours[i].InternalOnGainedOwnership();
+                if (ChildNetworkBehaviours[i].gameObject.activeInHierarchy)
+                {
+                    ChildNetworkBehaviours[i].InternalOnGainedOwnership();
+                }
+                else
+                {
+                    Debug.LogWarning($"{ChildNetworkBehaviours[i].gameObject.name} is disabled! Netcode for GameObjects does not support disabled NetworkBehaviours! The {ChildNetworkBehaviours[i].GetType().Name} component was skipped during ownership assignment!");
+                }
             }
         }
 
@@ -524,21 +573,21 @@ namespace Unity.Netcode
             }
         }
 
-        private bool m_IsReparented; // Did initial parent (came from the scene hierarchy) change at runtime?
         private ulong? m_LatestParent; // What is our last set parent NetworkObject's ID?
         private Transform m_CachedParent; // What is our last set parent Transform reference?
+        private bool m_CachedWorldPositionStays = true; // Used to preserve the world position stays parameter passed in TrySetParent
 
         internal void SetCachedParent(Transform parentTransform)
         {
             m_CachedParent = parentTransform;
         }
 
-        internal (bool IsReparented, ulong? LatestParent) GetNetworkParenting() => (m_IsReparented, m_LatestParent);
+        internal ulong? GetNetworkParenting() => m_LatestParent;
 
-        internal void SetNetworkParenting(bool isReparented, ulong? latestParent)
+        internal void SetNetworkParenting(ulong? latestParent, bool worldPositionStays)
         {
-            m_IsReparented = isReparented;
             m_LatestParent = latestParent;
+            m_CachedWorldPositionStays = worldPositionStays;
         }
 
         /// <summary>
@@ -549,7 +598,10 @@ namespace Unity.Netcode
         /// <returns>Whether or not reparenting was successful.</returns>
         public bool TrySetParent(Transform parent, bool worldPositionStays = true)
         {
-            return TrySetParent(parent.GetComponent<NetworkObject>(), worldPositionStays);
+            var networkObject = parent.GetComponent<NetworkObject>();
+
+            // If the parent doesn't have a NetworkObjet then return false, otherwise continue trying to parent
+            return networkObject == null ? false : TrySetParent(networkObject, worldPositionStays);
         }
 
         /// <summary>
@@ -560,7 +612,37 @@ namespace Unity.Netcode
         /// <returns>Whether or not reparenting was successful.</returns>
         public bool TrySetParent(GameObject parent, bool worldPositionStays = true)
         {
-            return TrySetParent(parent.GetComponent<NetworkObject>(), worldPositionStays);
+            // If we are removing ourself from a parent
+            if (parent == null)
+            {
+                return TrySetParent((NetworkObject)null, worldPositionStays);
+            }
+
+            var networkObject = parent.GetComponent<NetworkObject>();
+
+            // If the parent doesn't have a NetworkObjet then return false, otherwise continue trying to parent
+            return networkObject == null ? false : TrySetParent(networkObject, worldPositionStays);
+        }
+
+        /// <summary>
+        /// Used when despawning the parent, we want to preserve the cached WorldPositionStays value
+        /// </summary>
+        internal bool TryRemoveParentCachedWorldPositionStays()
+        {
+            return TrySetParent((NetworkObject)null, m_CachedWorldPositionStays);
+        }
+
+        /// <summary>
+        /// Removes the parent of the NetworkObject's transform
+        /// </summary>
+        /// <remarks>
+        /// This is a more convenient way to remove the parent without  having to cast the null value to either <see cref="GameObject"/> or <see cref="NetworkObject"/>
+        /// </remarks>
+        /// <param name="worldPositionStays">If true, the parent-relative position, scale and rotation are modified such that the object keeps the same world space position, rotation and scale as before.</param>
+        /// <returns></returns>
+        public bool TryRemoveParent(bool worldPositionStays = true)
+        {
+            return TrySetParent((NetworkObject)null, worldPositionStays);
         }
 
         /// <summary>
@@ -591,17 +673,21 @@ namespace Unity.Netcode
                 return false;
             }
 
+            if (parent != null && !parent.IsSpawned)
+            {
+                return false;
+            }
+            m_CachedWorldPositionStays = worldPositionStays;
+
             if (parent == null)
             {
-                return false;
+                transform.SetParent(null, worldPositionStays);
             }
-
-            if (!parent.IsSpawned)
+            else
             {
-                return false;
+                transform.SetParent(parent.transform, worldPositionStays);
             }
 
-            transform.SetParent(parent.transform, worldPositionStays);
             return true;
         }
 
@@ -637,12 +723,11 @@ namespace Unity.Netcode
                 Debug.LogException(new SpawnStateException($"{nameof(NetworkObject)} can only be reparented after being spawned"));
                 return;
             }
-
+            var removeParent = false;
             var parentTransform = transform.parent;
             if (parentTransform != null)
             {
-                var parentObject = transform.parent.GetComponent<NetworkObject>();
-                if (parentObject == null)
+                if (!transform.parent.TryGetComponent<NetworkObject>(out var parentObject))
                 {
                     transform.parent = m_CachedParent;
                     Debug.LogException(new InvalidParentException($"Invalid parenting, {nameof(NetworkObject)} moved under a non-{nameof(NetworkObject)} parent"));
@@ -661,19 +746,31 @@ namespace Unity.Netcode
             else
             {
                 m_LatestParent = null;
+                removeParent = m_CachedParent != null;
             }
 
-            m_IsReparented = true;
-            ApplyNetworkParenting();
+            ApplyNetworkParenting(removeParent);
 
             var message = new ParentSyncMessage
             {
                 NetworkObjectId = NetworkObjectId,
-                IsReparented = m_IsReparented,
                 IsLatestParentSet = m_LatestParent != null && m_LatestParent.HasValue,
-                LatestParent = m_LatestParent
+                LatestParent = m_LatestParent,
+                RemoveParent = removeParent,
+                WorldPositionStays = m_CachedWorldPositionStays,
+                Position = m_CachedWorldPositionStays ? transform.position : transform.localPosition,
+                Rotation = m_CachedWorldPositionStays ? transform.rotation : transform.localRotation,
+                Scale = transform.localScale,
             };
 
+            // We need to preserve the m_CachedWorldPositionStays value until after we create the message
+            // in order to assure any local space values changed/reset get applied properly. If our
+            // parent is null then go ahead and reset the m_CachedWorldPositionStays the default value.
+            if (parentTransform == null)
+            {
+                m_CachedWorldPositionStays = true;
+            }
+
             unsafe
             {
                 var maxCount = NetworkManager.ConnectedClientsIds.Count;
@@ -697,46 +794,94 @@ namespace Unity.Netcode
         // For instance, if we're spawning NetworkObject 5 and its parent is 10, what should happen if we do not have 10 yet?
         // let's say 10 is on the way to be replicated in a few frames and we could fix that parent-child relationship later.
         //
-        // If you couldn't find your parent, we put you into OrphanChildren set and everytime we spawn another NetworkObject locally due to replication,
+        // If you couldn't find your parent, we put you into OrphanChildren set and every time we spawn another NetworkObject locally due to replication,
         // we call CheckOrphanChildren() method and quickly iterate over OrphanChildren set and see if we can reparent/adopt one.
         internal static HashSet<NetworkObject> OrphanChildren = new HashSet<NetworkObject>();
 
-        internal bool ApplyNetworkParenting()
+        internal bool ApplyNetworkParenting(bool removeParent = false, bool ignoreNotSpawned = false)
         {
             if (!AutoObjectParentSync)
             {
                 return false;
             }
 
-            if (!IsSpawned)
+            // SPECIAL CASE:
+            // The ignoreNotSpawned is a special case scenario where a late joining client has joined
+            // and loaded one or more scenes that contain nested in-scene placed NetworkObject children
+            // yet the server's synchronization information does not indicate the NetworkObject in question
+            // has a parent. Under this scenario, we want to remove the parent before spawning and setting
+            // the transform values. This is the only scenario where the ignoreNotSpawned parameter is used.
+            if (!IsSpawned && !ignoreNotSpawned)
             {
                 return false;
             }
 
-            if (!m_IsReparented)
+            // Handle the first in-scene placed NetworkObject parenting scenarios. Once the m_LatestParent
+            // has been set, this will not be entered into again (i.e. the later code will be invoked and
+            // users will get notifications when the parent changes).
+            var isInScenePlaced = IsSceneObject.HasValue && IsSceneObject.Value;
+            if (transform.parent != null && !removeParent && !m_LatestParent.HasValue && isInScenePlaced)
             {
-                return true;
+                var parentNetworkObject = transform.parent.GetComponent<NetworkObject>();
+
+                // If parentNetworkObject is null then the parent is a GameObject without a NetworkObject component
+                // attached. Under this case, we preserve the hierarchy but we don't keep track of the parenting.
+                // Note: We only start tracking parenting if the user removes the child from the standard GameObject
+                // parent and then re-parents the child under a GameObject with a NetworkObject component attached.
+                if (parentNetworkObject == null)
+                {
+                    return true;
+                }
+                else // If the parent still isn't spawned add this to the orphaned children and return false
+                if (!parentNetworkObject.IsSpawned)
+                {
+                    OrphanChildren.Add(this);
+                    return false;
+                }
+                else
+                {
+                    // If we made it this far, go ahead and set the network parenting values
+                    // with the default WorldPoisitonSays value
+                    SetNetworkParenting(parentNetworkObject.NetworkObjectId, true);
+
+                    // Set the cached parent
+                    m_CachedParent = parentNetworkObject.transform;
+
+                    return true;
+                }
             }
 
-            if (m_LatestParent == null || !m_LatestParent.HasValue)
+            // If we are removing the parent or our latest parent is not set, then remove the parent
+            // removeParent is only set when:
+            //  - The server-side NetworkObject.OnTransformParentChanged is invoked and the parent is being removed
+            //  - The client-side when handling a ParentSyncMessage
+            // When clients are synchronizing only the m_LatestParent.HasValue will not have a value if there is no parent
+            // or a parent was removed prior to the client connecting (i.e. in-scene placed NetworkObjects)
+            if (removeParent || !m_LatestParent.HasValue)
             {
                 m_CachedParent = null;
-                transform.parent = null;
-
+                // We must use Transform.SetParent when taking WorldPositionStays into
+                // consideration, otherwise just setting transform.parent = null defaults
+                // to WorldPositionStays which can cause scaling issues if the parent's
+                // scale is not the default (Vetctor3.one) value.
+                transform.SetParent(null, m_CachedWorldPositionStays);
                 InvokeBehaviourOnNetworkObjectParentChanged(null);
                 return true;
             }
 
-            if (!NetworkManager.SpawnManager.SpawnedObjects.ContainsKey(m_LatestParent.Value))
+            // If we have a latest parent id but it hasn't been spawned yet, then add this instance to the orphanChildren
+            // HashSet and return false (i.e. parenting not applied yet)
+            if (m_LatestParent.HasValue && !NetworkManager.SpawnManager.SpawnedObjects.ContainsKey(m_LatestParent.Value))
             {
                 OrphanChildren.Add(this);
                 return false;
             }
 
+            // If we made it here, then parent this instance under the parentObject
             var parentObject = NetworkManager.SpawnManager.SpawnedObjects[m_LatestParent.Value];
 
             m_CachedParent = parentObject.transform;
-            transform.parent = parentObject.transform;
+            transform.SetParent(parentObject.transform, m_CachedWorldPositionStays);
 
             InvokeBehaviourOnNetworkObjectParentChanged(parentObject);
             return true;
@@ -764,7 +909,21 @@ namespace Unity.Netcode
 
             for (int i = 0; i < ChildNetworkBehaviours.Count; i++)
             {
-                ChildNetworkBehaviours[i].InternalOnNetworkSpawn();
+                if (ChildNetworkBehaviours[i].gameObject.activeInHierarchy)
+                {
+                    ChildNetworkBehaviours[i].InternalOnNetworkSpawn();
+                }
+                else
+                {
+                    Debug.LogWarning($"{ChildNetworkBehaviours[i].gameObject.name} is disabled! Netcode for GameObjects does not support spawning disabled NetworkBehaviours! The {ChildNetworkBehaviours[i].GetType().Name} component was skipped during spawn!");
+                }
+            }
+            for (int i = 0; i < ChildNetworkBehaviours.Count; i++)
+            {
+                if (ChildNetworkBehaviours[i].gameObject.activeInHierarchy)
+                {
+                    ChildNetworkBehaviours[i].VisibleOnNetworkSpawn();
+                }
             }
         }
 
@@ -813,12 +972,12 @@ namespace Unity.Netcode
             }
         }
 
-        internal void MarkVariablesDirty()
+        internal void MarkVariablesDirty(bool dirty)
         {
             for (int i = 0; i < ChildNetworkBehaviours.Count; i++)
             {
                 var behavior = ChildNetworkBehaviours[i];
-                behavior.MarkVariablesDirty();
+                behavior.MarkVariablesDirty(dirty);
             }
         }
 
@@ -907,7 +1066,6 @@ namespace Unity.Netcode
                 public bool HasParent;
                 public bool IsSceneObject;
                 public bool HasTransform;
-                public bool IsReparented;
             }
 
             public HeaderData Header;
@@ -920,6 +1078,7 @@ namespace Unity.Netcode
             {
                 public Vector3 Position;
                 public Quaternion Rotation;
+                public Vector3 Scale;
             }
 
             public TransformData Transform;
@@ -935,12 +1094,19 @@ namespace Unity.Netcode
 
             public int NetworkSceneHandle;
 
+            public bool WorldPositionStays;
+
             public unsafe void Serialize(FastBufferWriter writer)
             {
                 var writeSize = sizeof(HeaderData);
-                writeSize += Header.HasParent ? FastBufferWriter.GetWriteSize(ParentObjectId) : 0;
-                writeSize += Header.HasTransform ? FastBufferWriter.GetWriteSize(Transform) : 0;
-                writeSize += Header.IsReparented ? FastBufferWriter.GetWriteSize(IsLatestParentSet) + (IsLatestParentSet ? FastBufferWriter.GetWriteSize<ulong>() : 0) : 0;
+                if (Header.HasParent)
+                {
+                    writeSize += FastBufferWriter.GetWriteSize(ParentObjectId);
+                    writeSize += FastBufferWriter.GetWriteSize(WorldPositionStays);
+                    writeSize += FastBufferWriter.GetWriteSize(IsLatestParentSet);
+                    writeSize += IsLatestParentSet ? FastBufferWriter.GetWriteSize<ulong>() : 0;
+                }
+                writeSize += Header.HasTransform ? FastBufferWriter.GetWriteSize<TransformData>() : 0;
                 writeSize += Header.IsSceneObject ? FastBufferWriter.GetWriteSize<int>() : 0;
 
                 if (!writer.TryBeginWrite(writeSize))
@@ -953,6 +1119,12 @@ namespace Unity.Netcode
                 if (Header.HasParent)
                 {
                     writer.WriteValue(ParentObjectId);
+                    writer.WriteValue(WorldPositionStays);
+                    writer.WriteValue(IsLatestParentSet);
+                    if (IsLatestParentSet)
+                    {
+                        writer.WriteValue(LatestParent.Value);
+                    }
                 }
 
                 if (Header.HasTransform)
@@ -960,15 +1132,6 @@ namespace Unity.Netcode
                     writer.WriteValue(Transform);
                 }
 
-                if (Header.IsReparented)
-                {
-                    writer.WriteValue(IsLatestParentSet);
-                    if (IsLatestParentSet)
-                    {
-                        writer.WriteValue((ulong)LatestParent);
-                    }
-                }
-
                 // In-Scene NetworkObjects are uniquely identified NetworkPrefabs defined by their
                 // NetworkSceneHandle and GlobalObjectIdHash. Since each loaded scene has a unique
                 // handle, it provides us with a unique and persistent "scene prefab asset" instance.
@@ -989,19 +1152,41 @@ namespace Unity.Netcode
                     throw new OverflowException("Could not deserialize SceneObject: Out of buffer space.");
                 }
                 reader.ReadValue(out Header);
-                var readSize = Header.HasParent ? FastBufferWriter.GetWriteSize(ParentObjectId) : 0;
-                readSize += Header.HasTransform ? FastBufferWriter.GetWriteSize(Transform) : 0;
-                readSize += Header.IsReparented ? FastBufferWriter.GetWriteSize(IsLatestParentSet) + (IsLatestParentSet ? FastBufferWriter.GetWriteSize<ulong>() : 0) : 0;
+                var readSize = 0;
+                if (Header.HasParent)
+                {
+                    readSize += FastBufferWriter.GetWriteSize(ParentObjectId);
+                    readSize += FastBufferWriter.GetWriteSize(WorldPositionStays);
+                    readSize += FastBufferWriter.GetWriteSize(IsLatestParentSet);
+                    // We need to read at this point in order to get the IsLatestParentSet value
+                    if (!reader.TryBeginRead(readSize))
+                    {
+                        throw new OverflowException("Could not deserialize SceneObject: Out of buffer space.");
+                    }
+
+                    // Read the initial parenting related properties
+                    reader.ReadValue(out ParentObjectId);
+                    reader.ReadValue(out WorldPositionStays);
+                    reader.ReadValue(out IsLatestParentSet);
+
+                    // Now calculate the remaining bytes to read
+                    readSize = 0;
+                    readSize += IsLatestParentSet ? FastBufferWriter.GetWriteSize<ulong>() : 0;
+                }
+
+                readSize += Header.HasTransform ? FastBufferWriter.GetWriteSize<TransformData>() : 0;
                 readSize += Header.IsSceneObject ? FastBufferWriter.GetWriteSize<int>() : 0;
 
+                // Try to begin reading the remaining bytes
                 if (!reader.TryBeginRead(readSize))
                 {
                     throw new OverflowException("Could not deserialize SceneObject: Out of buffer space.");
                 }
 
-                if (Header.HasParent)
+                if (IsLatestParentSet)
                 {
-                    reader.ReadValue(out ParentObjectId);
+                    reader.ReadValueSafe(out ulong latestParent);
+                    LatestParent = latestParent;
                 }
 
                 if (Header.HasTransform)
@@ -1009,16 +1194,6 @@ namespace Unity.Netcode
                     reader.ReadValue(out Transform);
                 }
 
-                if (Header.IsReparented)
-                {
-                    reader.ReadValue(out IsLatestParentSet);
-                    if (IsLatestParentSet)
-                    {
-                        reader.ReadValueSafe(out ulong latestParent);
-                        LatestParent = latestParent;
-                    }
-                }
-
                 // In-Scene NetworkObjects are uniquely identified NetworkPrefabs defined by their
                 // NetworkSceneHandle and GlobalObjectIdHash. Since each loaded scene has a unique
                 // handle, it provides us with a unique and persistent "scene prefab asset" instance.
@@ -1031,6 +1206,14 @@ namespace Unity.Netcode
             }
         }
 
+        internal void PostNetworkVariableWrite()
+        {
+            for (int k = 0; k < ChildNetworkBehaviours.Count; k++)
+            {
+                ChildNetworkBehaviours[k].PostNetworkVariableWrite();
+            }
+        }
+
         internal SceneObject GetMessageSceneObject(ulong targetClientId)
         {
             var obj = new SceneObject
@@ -1054,25 +1237,12 @@ namespace Unity.Netcode
                 parentNetworkObject = transform.parent.GetComponent<NetworkObject>();
             }
 
-            if (parentNetworkObject)
+            if (parentNetworkObject != null)
             {
                 obj.Header.HasParent = true;
                 obj.ParentObjectId = parentNetworkObject.NetworkObjectId;
-            }
-            if (IncludeTransformWhenSpawning == null || IncludeTransformWhenSpawning(OwnerClientId))
-            {
-                obj.Header.HasTransform = true;
-                obj.Transform = new SceneObject.TransformData
-                {
-                    Position = transform.position,
-                    Rotation = transform.rotation
-                };
-            }
-
-            var (isReparented, latestParent) = GetNetworkParenting();
-            obj.Header.IsReparented = isReparented;
-            if (isReparented)
-            {
+                obj.WorldPositionStays = m_CachedWorldPositionStays;
+                var latestParent = GetNetworkParenting();
                 var isLatestParentSet = latestParent != null && latestParent.HasValue;
                 obj.IsLatestParentSet = isLatestParentSet;
                 if (isLatestParentSet)
@@ -1081,6 +1251,25 @@ namespace Unity.Netcode
                 }
             }
 
+            if (IncludeTransformWhenSpawning == null || IncludeTransformWhenSpawning(OwnerClientId))
+            {
+                obj.Header.HasTransform = true;
+                obj.Transform = new SceneObject.TransformData
+                {
+                    // If we are parented and we have the m_CachedWorldPositionStays disabled, then use local space
+                    // values as opposed world space values.
+                    Position = parentNetworkObject && !m_CachedWorldPositionStays ? transform.localPosition : transform.position,
+                    Rotation = parentNetworkObject && !m_CachedWorldPositionStays ? transform.localRotation : transform.rotation,
+
+                    // We only use the lossyScale if the NetworkObject has a parent. Multi-generation nested children scales can
+                    // impact the final scale of the child NetworkObject in question. The solution is to use the lossy scale
+                    // which can be thought of as "world space scale".
+                    // More information:
+                    // https://docs.unity3d.com/ScriptReference/Transform-lossyScale.html
+                    Scale = parentNetworkObject && !m_CachedWorldPositionStays ? transform.localScale : transform.lossyScale,
+                };
+            }
+
             return obj;
         }
 
@@ -1094,33 +1283,8 @@ namespace Unity.Netcode
         /// <returns>optional to use NetworkObject deserialized</returns>
         internal static NetworkObject AddSceneObject(in SceneObject sceneObject, FastBufferReader variableData, NetworkManager networkManager)
         {
-            Vector3? position = null;
-            Quaternion? rotation = null;
-            ulong? parentNetworkId = null;
-            int? networkSceneHandle = null;
-
-            if (sceneObject.Header.HasTransform)
-            {
-                position = sceneObject.Transform.Position;
-                rotation = sceneObject.Transform.Rotation;
-            }
-
-            if (sceneObject.Header.HasParent)
-            {
-                parentNetworkId = sceneObject.ParentObjectId;
-            }
-
-            if (sceneObject.Header.IsSceneObject)
-            {
-                networkSceneHandle = sceneObject.NetworkSceneHandle;
-            }
-
             //Attempt to create a local NetworkObject
-            var networkObject = networkManager.SpawnManager.CreateLocalNetworkObject(
-                sceneObject.Header.IsSceneObject, sceneObject.Header.Hash,
-                sceneObject.Header.OwnerClientId, parentNetworkId, networkSceneHandle, position, rotation, sceneObject.Header.IsReparented);
-
-            networkObject?.SetNetworkParenting(sceneObject.Header.IsReparented, sceneObject.LatestParent);
+            var networkObject = networkManager.SpawnManager.CreateLocalNetworkObject(sceneObject);
 
             if (networkObject == null)
             {
@@ -1135,7 +1299,7 @@ namespace Unity.Netcode
                 return null;
             }
 
-            // Spawn the NetworkObject(
+            // Spawn the NetworkObject
             networkManager.SpawnManager.SpawnNetworkObjectLocally(networkObject, sceneObject, variableData, false);
 
             return networkObject;
@@ -1164,5 +1328,21 @@ namespace Unity.Netcode
 
             return GlobalObjectIdHash;
         }
+
+        /// <summary>
+        /// Removes a NetworkBehaviour from the ChildNetworkBehaviours list when destroyed
+        /// while the NetworkObject is still spawned.
+        /// </summary>
+        internal void OnNetworkBehaviourDestroyed(NetworkBehaviour networkBehaviour)
+        {
+            if (networkBehaviour.IsSpawned && IsSpawned)
+            {
+                if (NetworkManager.LogLevel == LogLevel.Developer)
+                {
+                    NetworkLog.LogWarning($"{nameof(NetworkBehaviour)}-{networkBehaviour.name} is being destroyed while {nameof(NetworkObject)}-{name} is still spawned! (could break state synchronization)");
+                }
+                ChildNetworkBehaviours.Remove(networkBehaviour);
+            }
+        }
     }
 }

Runtime/Messaging/Messages/ConnectionApprovedMessage.cs

@@ -79,6 +79,7 @@ namespace Unity.Netcode
             networkManager.NetworkTickSystem.Reset(networkManager.NetworkTimeSystem.LocalTime, networkManager.NetworkTimeSystem.ServerTime);
 
             networkManager.LocalClient = new NetworkClient() { ClientId = networkManager.LocalClientId };
+            networkManager.IsApproved = true;
 
             // Only if scene management is disabled do we handle NetworkObject synchronization at this point
             if (!networkManager.NetworkConfig.EnableSceneManagement)

Runtime/Messaging/Messages/OrderingMessage.cs

@@ -0,0 +1,50 @@
+using System;
+
+namespace Unity.Netcode
+{
+    /// <summary>
+    /// Upon connecting, the host sends a series of OrderingMessage to the client so that it can make sure both sides
+    /// have the same message types in the same positions in
+    /// - MessagingSystem.m_MessageHandlers
+    /// - MessagingSystem.m_ReverseTypeMap
+    /// even if one side has extra messages (compilation, version, patch, or platform differences, etc...)
+    ///
+    /// The ConnectionRequestedMessage, ConnectionApprovedMessage and OrderingMessage are prioritized at the beginning
+    /// of the mapping, to guarantee they can be exchanged before the two sides share their ordering
+    /// The sorting used in also stable so that even if MessageType names share hashes, it will work most of the time
+    /// </summary>
+    internal struct OrderingMessage : INetworkMessage
+    {
+        public int Order;
+        public uint Hash;
+
+        public void Serialize(FastBufferWriter writer)
+        {
+            if (!writer.TryBeginWrite(FastBufferWriter.GetWriteSize(Order) + FastBufferWriter.GetWriteSize(Hash)))
+            {
+                throw new OverflowException($"Not enough space in the buffer to write {nameof(OrderingMessage)}");
+            }
+
+            writer.WriteValue(Order);
+            writer.WriteValue(Hash);
+        }
+
+        public bool Deserialize(FastBufferReader reader, ref NetworkContext context)
+        {
+            if (!reader.TryBeginRead(FastBufferWriter.GetWriteSize(Order) + FastBufferWriter.GetWriteSize(Hash)))
+            {
+                throw new OverflowException($"Not enough data in the buffer to read {nameof(OrderingMessage)}");
+            }
+
+            reader.ReadValue(out Order);
+            reader.ReadValue(out Hash);
+
+            return true;
+        }
+
+        public void Handle(ref NetworkContext context)
+        {
+            ((NetworkManager)context.SystemOwner).MessagingSystem.ReorderMessage(Order, Hash);
+        }
+    }
+}

Runtime/Messaging/Messages/OrderingMessage.cs.meta

@@ -1,5 +1,5 @@
 fileFormatVersion: 2
-guid: c2e5a740c1abd4315801e3f26ecf8adb
+guid: 3ada9e8fd5bf94b1f9a6a21531c8a3ee
 MonoImporter:
   externalObjects: {}
   serializedVersion: 2

Runtime/Messaging/Messages/ParentSyncMessage.cs

@@ -1,10 +1,12 @@
+using UnityEngine;
+
 namespace Unity.Netcode
 {
     internal struct ParentSyncMessage : INetworkMessage
     {
         public ulong NetworkObjectId;
 
-        public bool IsReparented;
+        public bool WorldPositionStays;
 
         //If(Metadata.IsReparented)
         public bool IsLatestParentSet;
@@ -12,18 +14,36 @@ namespace Unity.Netcode
         //If(IsLatestParentSet)
         public ulong? LatestParent;
 
+        // Is set when the parent should be removed (similar to IsReparented functionality but only for removing the parent)
+        public bool RemoveParent;
+
+        // These additional properties are used to synchronize clients with the current position,
+        // rotation, and scale after parenting/de-parenting (world/local space relative). This
+        // allows users to control the final child's transform values without having to have a
+        // NetworkTransform component on the child. (i.e. picking something up)
+        public Vector3 Position;
+        public Quaternion Rotation;
+        public Vector3 Scale;
+
         public void Serialize(FastBufferWriter writer)
         {
-            writer.WriteValueSafe(NetworkObjectId);
-            writer.WriteValueSafe(IsReparented);
-            if (IsReparented)
+            BytePacker.WriteValuePacked(writer, NetworkObjectId);
+            writer.WriteValueSafe(RemoveParent);
+            writer.WriteValueSafe(WorldPositionStays);
+            if (!RemoveParent)
             {
                 writer.WriteValueSafe(IsLatestParentSet);
+
                 if (IsLatestParentSet)
                 {
-                    writer.WriteValueSafe((ulong)LatestParent);
+                    BytePacker.WriteValueBitPacked(writer, (ulong)LatestParent);
                 }
             }
+
+            // Whether parenting or removing a parent, we always update the position, rotation, and scale
+            writer.WriteValueSafe(Position);
+            writer.WriteValueSafe(Rotation);
+            writer.WriteValueSafe(Scale);
         }
 
         public bool Deserialize(FastBufferReader reader, ref NetworkContext context)
@@ -34,24 +54,30 @@ namespace Unity.Netcode
                 return false;
             }
 
-            reader.ReadValueSafe(out NetworkObjectId);
-            reader.ReadValueSafe(out IsReparented);
-            if (IsReparented)
+            ByteUnpacker.ReadValuePacked(reader, out NetworkObjectId);
+            reader.ReadValueSafe(out RemoveParent);
+            reader.ReadValueSafe(out WorldPositionStays);
+            if (!RemoveParent)
             {
                 reader.ReadValueSafe(out IsLatestParentSet);
+
                 if (IsLatestParentSet)
                 {
-                    reader.ReadValueSafe(out ulong latestParent);
+                    ByteUnpacker.ReadValueBitPacked(reader, out ulong latestParent);
                     LatestParent = latestParent;
                 }
             }
 
+            // Whether parenting or removing a parent, we always update the position, rotation, and scale
+            reader.ReadValueSafe(out Position);
+            reader.ReadValueSafe(out Rotation);
+            reader.ReadValueSafe(out Scale);
+
             if (!networkManager.SpawnManager.SpawnedObjects.ContainsKey(NetworkObjectId))
             {
                 networkManager.DeferredMessageManager.DeferMessage(IDeferredMessageManager.TriggerType.OnSpawn, NetworkObjectId, reader, ref context);
                 return false;
             }
-
             return true;
         }
 
@@ -59,8 +85,22 @@ namespace Unity.Netcode
         {
             var networkManager = (NetworkManager)context.SystemOwner;
             var networkObject = networkManager.SpawnManager.SpawnedObjects[NetworkObjectId];
-            networkObject.SetNetworkParenting(IsReparented, LatestParent);
-            networkObject.ApplyNetworkParenting();
+            networkObject.SetNetworkParenting(LatestParent, WorldPositionStays);
+            networkObject.ApplyNetworkParenting(RemoveParent);
+
+            // We set all of the transform values after parenting as they are
+            // the values of the server-side post-parenting transform values
+            if (!WorldPositionStays)
+            {
+                networkObject.transform.localPosition = Position;
+                networkObject.transform.localRotation = Rotation;
+            }
+            else
+            {
+                networkObject.transform.position = Position;
+                networkObject.transform.rotation = Rotation;
+            }
+            networkObject.transform.localScale = Scale;
         }
     }
 }

Runtime/Messaging/MessagingSystem.cs

@@ -8,6 +8,11 @@ using UnityEngine;
 
 namespace Unity.Netcode
 {
+    internal class HandlerNotRegisteredException : SystemException
+    {
+        public HandlerNotRegisteredException() { }
+        public HandlerNotRegisteredException(string issue) : base(issue) { }
+    }
 
     internal class InvalidMessageStructureException : SystemException
     {
@@ -44,8 +49,9 @@ namespace Unity.Netcode
 
         private NativeList<ReceiveQueueItem> m_IncomingMessageQueue = new NativeList<ReceiveQueueItem>(16, Allocator.Persistent);
 
-        private MessageHandler[] m_MessageHandlers = new MessageHandler[255];
-        private Type[] m_ReverseTypeMap = new Type[255];
+        // These array will grow as we need more message handlers. 4 is just a starting size.
+        private MessageHandler[] m_MessageHandlers = new MessageHandler[4];
+        private Type[] m_ReverseTypeMap = new Type[4];
 
         private Dictionary<Type, uint> m_MessageTypes = new Dictionary<Type, uint>();
         private Dictionary<ulong, NativeList<SendQueueItem>> m_SendQueues = new Dictionary<ulong, NativeList<SendQueueItem>>();
@@ -59,6 +65,7 @@ namespace Unity.Netcode
 
         internal Type[] MessageTypes => m_ReverseTypeMap;
         internal MessageHandler[] MessageHandlers => m_MessageHandlers;
+
         internal uint MessageHandlerCount => m_HighMessageType;
 
         internal uint GetMessageType(Type t)
@@ -75,6 +82,35 @@ namespace Unity.Netcode
             public MessageHandler Handler;
         }
 
+        internal List<MessageWithHandler> PrioritizeMessageOrder(List<MessageWithHandler> allowedTypes)
+        {
+            var prioritizedTypes = new List<MessageWithHandler>();
+
+            // first pass puts the priority message in the first indices
+            // Those are the messages that must be delivered in order to allow re-ordering the others later
+            foreach (var t in allowedTypes)
+            {
+                if (t.MessageType.FullName == "Unity.Netcode.ConnectionRequestMessage" ||
+                    t.MessageType.FullName == "Unity.Netcode.ConnectionApprovedMessage" ||
+                    t.MessageType.FullName == "Unity.Netcode.OrderingMessage")
+                {
+                    prioritizedTypes.Add(t);
+                }
+            }
+
+            foreach (var t in allowedTypes)
+            {
+                if (t.MessageType.FullName != "Unity.Netcode.ConnectionRequestMessage" &&
+                    t.MessageType.FullName != "Unity.Netcode.ConnectionApprovedMessage" &&
+                    t.MessageType.FullName != "Unity.Netcode.OrderingMessage")
+                {
+                    prioritizedTypes.Add(t);
+                }
+            }
+
+            return prioritizedTypes;
+        }
+
         public MessagingSystem(IMessageSender messageSender, object owner, IMessageProvider provider = null)
         {
             try
@@ -89,6 +125,7 @@ namespace Unity.Netcode
                 var allowedTypes = provider.GetMessages();
 
                 allowedTypes.Sort((a, b) => string.CompareOrdinal(a.MessageType.FullName, b.MessageType.FullName));
+                allowedTypes = PrioritizeMessageOrder(allowedTypes);
                 foreach (var type in allowedTypes)
                 {
                     RegisterMessageType(type);
@@ -143,6 +180,13 @@ namespace Unity.Netcode
 
         private void RegisterMessageType(MessageWithHandler messageWithHandler)
         {
+            // if we are out of space, perform amortized linear growth
+            if (m_HighMessageType == m_MessageHandlers.Length)
+            {
+                Array.Resize(ref m_MessageHandlers, 2 * m_MessageHandlers.Length);
+                Array.Resize(ref m_ReverseTypeMap, 2 * m_ReverseTypeMap.Length);
+            }
+
             m_MessageHandlers[m_HighMessageType] = messageWithHandler.Handler;
             m_ReverseTypeMap[m_HighMessageType] = messageWithHandler.MessageType;
             m_MessageTypes[messageWithHandler.MessageType] = m_HighMessageType++;
@@ -226,6 +270,70 @@ namespace Unity.Netcode
             return true;
         }
 
+        // Moves the handler for the type having hash `targetHash` to the `desiredOrder` position, in the handler list
+        // This allows the server to tell the client which id it is using for which message and make sure the right
+        // message is used when deserializing.
+        internal void ReorderMessage(int desiredOrder, uint targetHash)
+        {
+            if (desiredOrder < 0)
+            {
+                throw new ArgumentException("ReorderMessage desiredOrder must be positive");
+            }
+
+            if (desiredOrder < m_ReverseTypeMap.Length &&
+                XXHash.Hash32(m_ReverseTypeMap[desiredOrder].FullName) == targetHash)
+            {
+                // matching positions and hashes. All good.
+                return;
+            }
+
+            Debug.Log($"Unexpected hash for {desiredOrder}");
+
+            // Since the message at `desiredOrder` is not the expected one,
+            // insert an empty placeholder and move the messages down
+            var typesAsList = new List<Type>(m_ReverseTypeMap);
+
+            typesAsList.Insert(desiredOrder, null);
+            var handlersAsList = new List<MessageHandler>(m_MessageHandlers);
+            handlersAsList.Insert(desiredOrder, null);
+
+            // we added a dummy message, bump the end up
+            m_HighMessageType++;
+
+            // Here, we rely on the server telling us about all messages, in order.
+            // So, we know the handlers before desiredOrder are correct.
+            // We start at desiredOrder to not shift them when we insert.
+            int position = desiredOrder;
+            bool found = false;
+            while (position < typesAsList.Count)
+            {
+                if (typesAsList[position] != null &&
+                    XXHash.Hash32(typesAsList[position].FullName) == targetHash)
+                {
+                    found = true;
+                    break;
+                }
+
+                position++;
+            }
+
+            if (found)
+            {
+                // Copy the handler and type to the right index
+
+                typesAsList[desiredOrder] = typesAsList[position];
+                handlersAsList[desiredOrder] = handlersAsList[position];
+                typesAsList.RemoveAt(position);
+                handlersAsList.RemoveAt(position);
+
+                // we removed a copy after moving a message, reduce the high message index
+                m_HighMessageType--;
+            }
+
+            m_ReverseTypeMap = typesAsList.ToArray();
+            m_MessageHandlers = handlersAsList.ToArray();
+        }
+
         public void HandleMessage(in MessageHeader header, FastBufferReader reader, ulong senderId, float timestamp, int serializedHeaderSize)
         {
             if (header.MessageType >= m_HighMessageType)
@@ -259,18 +367,29 @@ namespace Unity.Netcode
             var handler = m_MessageHandlers[header.MessageType];
             using (reader)
             {
-                // No user-land message handler exceptions should escape the receive loop.
-                // If an exception is throw, the message is ignored.
-                // Example use case: A bad message is received that can't be deserialized and throws
-                // an OverflowException because it specifies a length greater than the number of bytes in it
-                // for some dynamic-length value.
-                try
+                // This will also log an exception is if the server knows about a message type the client doesn't know
+                // about. In this case the handler will be null. It is still an issue the user must deal with: If the
+                // two connecting builds know about different messages, the server should not send a message to a client
+                // that doesn't know about it
+                if (handler == null)
                 {
-                    handler.Invoke(reader, ref context, this);
+                    Debug.LogException(new HandlerNotRegisteredException(header.MessageType.ToString()));
                 }
-                catch (Exception e)
+                else
                 {
-                    Debug.LogException(e);
+                    // No user-land message handler exceptions should escape the receive loop.
+                    // If an exception is throw, the message is ignored.
+                    // Example use case: A bad message is received that can't be deserialized and throws
+                    // an OverflowException because it specifies a length greater than the number of bytes in it
+                    // for some dynamic-length value.
+                    try
+                    {
+                        handler.Invoke(reader, ref context, this);
+                    }
+                    catch (Exception e)
+                    {
+                        Debug.LogException(e);
+                    }
                 }
             }
             for (var hookIdx = 0; hookIdx < m_Hooks.Count; ++hookIdx)

Runtime/Metrics/NetworkMetrics.cs

@@ -5,17 +5,14 @@ using Unity.Multiplayer.Tools;
 using Unity.Multiplayer.Tools.MetricTypes;
 using Unity.Multiplayer.Tools.NetStats;
 using Unity.Profiling;
-using UnityEngine;
 
 namespace Unity.Netcode
 {
     internal class NetworkMetrics : INetworkMetrics
     {
-        const ulong k_MaxMetricsPerFrame = 1000L;
-
-        static Dictionary<uint, string> s_SceneEventTypeNames;
-
-        static ProfilerMarker s_FrameDispatch = new ProfilerMarker($"{nameof(NetworkMetrics)}.DispatchFrame");
+        private const ulong k_MaxMetricsPerFrame = 1000L;
+        private static Dictionary<uint, string> s_SceneEventTypeNames;
+        private static ProfilerMarker s_FrameDispatch = new ProfilerMarker($"{nameof(NetworkMetrics)}.DispatchFrame");
 
         static NetworkMetrics()
         {
@@ -531,7 +528,7 @@ namespace Unity.Netcode
         }
     }
 
-        internal class NetcodeObserver
+    internal class NetcodeObserver
     {
         public static IMetricObserver Observer { get; } = MetricObserverFactory.Construct();
     }

Runtime/Metrics/NetworkObjectProvider.cs

@@ -4,7 +4,7 @@ using UnityEngine;
 
 namespace Unity.Netcode
 {
-    class NetworkObjectProvider : INetworkObjectProvider
+    internal class NetworkObjectProvider : INetworkObjectProvider
     {
         private readonly NetworkManager m_NetworkManager;
 
@@ -15,7 +15,7 @@ namespace Unity.Netcode
 
         public Object GetNetworkObject(ulong networkObjectId)
         {
-            if(m_NetworkManager.SpawnManager.SpawnedObjects.TryGetValue(networkObjectId, out NetworkObject value))
+            if (m_NetworkManager.SpawnManager.SpawnedObjects.TryGetValue(networkObjectId, out NetworkObject value))
             {
                 return value;
             }

Runtime/NetworkVariable/Collections/NetworkList.cs

@@ -1,6 +1,7 @@
 using System;
 using System.Collections.Generic;
 using Unity.Collections;
+using UnityEngine;
 
 namespace Unity.Netcode
 {
@@ -11,7 +12,6 @@ namespace Unity.Netcode
     public class NetworkList<T> : NetworkVariableBase where T : unmanaged, IEquatable<T>
     {
         private NativeList<T> m_List = new NativeList<T>(64, Allocator.Persistent);
-        private NativeList<T> m_ListAtLastReset = new NativeList<T>(64, Allocator.Persistent);
         private NativeList<NetworkListEvent<T>> m_DirtyEvents = new NativeList<NetworkListEvent<T>>(64, Allocator.Persistent);
 
         /// <summary>
@@ -39,9 +39,13 @@ namespace Unity.Netcode
             NetworkVariableWritePermission writePerm = DefaultWritePerm)
             : base(readPerm, writePerm)
         {
-            foreach (var value in values)
+            // allow null IEnumerable<T> to mean "no values"
+            if (values != null)
             {
-                m_List.Add(value);
+                foreach (var value in values)
+                {
+                    m_List.Add(value);
+                }
             }
         }
 
@@ -52,7 +56,6 @@ namespace Unity.Netcode
             if (m_DirtyEvents.Length > 0)
             {
                 m_DirtyEvents.Clear();
-                m_ListAtLastReset.CopyFrom(m_List);
             }
         }
 
@@ -63,6 +66,18 @@ namespace Unity.Netcode
             return base.IsDirty() || m_DirtyEvents.Length > 0;
         }
 
+        internal void MarkNetworkObjectDirty()
+        {
+            if (m_NetworkBehaviour == null)
+            {
+                Debug.LogWarning($"NetworkList is written to, but doesn't know its NetworkBehaviour yet. " +
+                                 "Are you modifying a NetworkList before the NetworkObject is spawned?");
+                return;
+            }
+
+            m_NetworkBehaviour.NetworkManager.MarkNetworkObjectDirty(m_NetworkBehaviour.NetworkObject);
+        }
+
         /// <inheritdoc />
         public override void WriteDelta(FastBufferWriter writer)
         {
@@ -122,10 +137,10 @@ namespace Unity.Netcode
         /// <inheritdoc />
         public override void WriteField(FastBufferWriter writer)
         {
-            writer.WriteValueSafe((ushort)m_ListAtLastReset.Length);
-            for (int i = 0; i < m_ListAtLastReset.Length; i++)
+            writer.WriteValueSafe((ushort)m_List.Length);
+            for (int i = 0; i < m_List.Length; i++)
             {
-                NetworkVariableSerialization<T>.Write(writer, ref m_ListAtLastReset.ElementAt(i));
+                NetworkVariableSerialization<T>.Write(writer, ref m_List.ElementAt(i));
             }
         }
 
@@ -136,7 +151,8 @@ namespace Unity.Netcode
             reader.ReadValueSafe(out ushort count);
             for (int i = 0; i < count; i++)
             {
-                NetworkVariableSerialization<T>.Read(reader, out T value);
+                var value = new T();
+                NetworkVariableSerialization<T>.Read(reader, ref value);
                 m_List.Add(value);
             }
         }
@@ -152,7 +168,8 @@ namespace Unity.Netcode
                 {
                     case NetworkListEvent<T>.EventType.Add:
                         {
-                            NetworkVariableSerialization<T>.Read(reader, out T value);
+                            var value = new T();
+                            NetworkVariableSerialization<T>.Read(reader, ref value);
                             m_List.Add(value);
 
                             if (OnListChanged != null)
@@ -173,15 +190,25 @@ namespace Unity.Netcode
                                     Index = m_List.Length - 1,
                                     Value = m_List[m_List.Length - 1]
                                 });
+                                MarkNetworkObjectDirty();
                             }
                         }
                         break;
                     case NetworkListEvent<T>.EventType.Insert:
                         {
                             reader.ReadValueSafe(out int index);
-                            NetworkVariableSerialization<T>.Read(reader, out T value);
-                            m_List.InsertRangeWithBeginEnd(index, index + 1);
-                            m_List[index] = value;
+                            var value = new T();
+                            NetworkVariableSerialization<T>.Read(reader, ref value);
+
+                            if (index < m_List.Length)
+                            {
+                                m_List.InsertRangeWithBeginEnd(index, index + 1);
+                                m_List[index] = value;
+                            }
+                            else
+                            {
+                                m_List.Add(value);
+                            }
 
                             if (OnListChanged != null)
                             {
@@ -201,12 +228,14 @@ namespace Unity.Netcode
                                     Index = index,
                                     Value = m_List[index]
                                 });
+                                MarkNetworkObjectDirty();
                             }
                         }
                         break;
                     case NetworkListEvent<T>.EventType.Remove:
                         {
-                            NetworkVariableSerialization<T>.Read(reader, out T value);
+                            var value = new T();
+                            NetworkVariableSerialization<T>.Read(reader, ref value);
                             int index = m_List.IndexOf(value);
                             if (index == -1)
                             {
@@ -233,6 +262,7 @@ namespace Unity.Netcode
                                     Index = index,
                                     Value = value
                                 });
+                                MarkNetworkObjectDirty();
                             }
                         }
                         break;
@@ -260,13 +290,15 @@ namespace Unity.Netcode
                                     Index = index,
                                     Value = value
                                 });
+                                MarkNetworkObjectDirty();
                             }
                         }
                         break;
                     case NetworkListEvent<T>.EventType.Value:
                         {
                             reader.ReadValueSafe(out int index);
-                            NetworkVariableSerialization<T>.Read(reader, out T value);
+                            var value = new T();
+                            NetworkVariableSerialization<T>.Read(reader, ref value);
                             if (index >= m_List.Length)
                             {
                                 throw new Exception("Shouldn't be here, index is higher than list length");
@@ -295,6 +327,7 @@ namespace Unity.Netcode
                                     Value = value,
                                     PreviousValue = previousValue
                                 });
+                                MarkNetworkObjectDirty();
                             }
                         }
                         break;
@@ -317,6 +350,7 @@ namespace Unity.Netcode
                                 {
                                     Type = eventType
                                 });
+                                MarkNetworkObjectDirty();
                             }
                         }
                         break;
@@ -339,6 +373,12 @@ namespace Unity.Netcode
         /// <inheritdoc />
         public void Add(T item)
         {
+            // check write permissions
+            if (!CanClientWrite(m_NetworkBehaviour.NetworkManager.LocalClientId))
+            {
+                throw new InvalidOperationException("Client is not allowed to write to this NetworkList");
+            }
+
             m_List.Add(item);
 
             var listEvent = new NetworkListEvent<T>()
@@ -354,6 +394,12 @@ namespace Unity.Netcode
         /// <inheritdoc />
         public void Clear()
         {
+            // check write permissions
+            if (!CanClientWrite(m_NetworkBehaviour.NetworkManager.LocalClientId))
+            {
+                throw new InvalidOperationException("Client is not allowed to write to this NetworkList");
+            }
+
             m_List.Clear();
 
             var listEvent = new NetworkListEvent<T>()
@@ -374,6 +420,12 @@ namespace Unity.Netcode
         /// <inheritdoc />
         public bool Remove(T item)
         {
+            // check write permissions
+            if (!CanClientWrite(m_NetworkBehaviour.NetworkManager.LocalClientId))
+            {
+                throw new InvalidOperationException("Client is not allowed to write to this NetworkList");
+            }
+
             int index = NativeArrayExtensions.IndexOf(m_List, item);
             if (index == -1)
             {
@@ -403,8 +455,21 @@ namespace Unity.Netcode
         /// <inheritdoc />
         public void Insert(int index, T item)
         {
-            m_List.InsertRangeWithBeginEnd(index, index + 1);
-            m_List[index] = item;
+            // check write permissions
+            if (!CanClientWrite(m_NetworkBehaviour.NetworkManager.LocalClientId))
+            {
+                throw new InvalidOperationException("Client is not allowed to write to this NetworkList");
+            }
+
+            if (index < m_List.Length)
+            {
+                m_List.InsertRangeWithBeginEnd(index, index + 1);
+                m_List[index] = item;
+            }
+            else
+            {
+                m_List.Add(item);
+            }
 
             var listEvent = new NetworkListEvent<T>()
             {
@@ -419,6 +484,12 @@ namespace Unity.Netcode
         /// <inheritdoc />
         public void RemoveAt(int index)
         {
+            // check write permissions
+            if (!CanClientWrite(m_NetworkBehaviour.NetworkManager.LocalClientId))
+            {
+                throw new InvalidOperationException("Client is not allowed to write to this NetworkList");
+            }
+
             m_List.RemoveAt(index);
 
             var listEvent = new NetworkListEvent<T>()
@@ -436,13 +507,21 @@ namespace Unity.Netcode
             get => m_List[index];
             set
             {
+                // check write permissions
+                if (!CanClientWrite(m_NetworkBehaviour.NetworkManager.LocalClientId))
+                {
+                    throw new InvalidOperationException("Client is not allowed to write to this NetworkList");
+                }
+
+                var previousValue = m_List[index];
                 m_List[index] = value;
 
                 var listEvent = new NetworkListEvent<T>()
                 {
                     Type = NetworkListEvent<T>.EventType.Value,
                     Index = index,
-                    Value = value
+                    Value = value,
+                    PreviousValue = previousValue
                 };
 
                 HandleAddListEvent(listEvent);
@@ -452,6 +531,7 @@ namespace Unity.Netcode
         private void HandleAddListEvent(NetworkListEvent<T> listEvent)
         {
             m_DirtyEvents.Add(listEvent);
+            MarkNetworkObjectDirty();
             OnListChanged?.Invoke(listEvent);
         }
 
@@ -475,7 +555,6 @@ namespace Unity.Netcode
         public override void Dispose()
         {
             m_List.Dispose();
-            m_ListAtLastReset.Dispose();
             m_DirtyEvents.Dispose();
         }
     }

Runtime/NetworkVariable/NetworkVariable.cs

@@ -1,7 +1,5 @@
 using UnityEngine;
 using System;
-using System.Runtime.CompilerServices;
-using Unity.Collections.LowLevel.Unsafe;
 
 namespace Unity.Netcode
 {
@@ -10,7 +8,7 @@ namespace Unity.Netcode
     /// </summary>
     /// <typeparam name="T">the unmanaged type for <see cref="NetworkVariable{T}"/> </typeparam>
     [Serializable]
-    public class NetworkVariable<T> : NetworkVariableBase where T : unmanaged
+    public class NetworkVariable<T> : NetworkVariableBase
     {
         /// <summary>
         /// Delegate type for value changed event
@@ -52,7 +50,7 @@ namespace Unity.Netcode
             set
             {
                 // Compare bitwise
-                if (ValueEquals(ref m_InternalValue, ref value))
+                if (NetworkVariableSerialization<T>.AreEqual(ref m_InternalValue, ref value))
                 {
                     return;
                 }
@@ -66,20 +64,6 @@ namespace Unity.Netcode
             }
         }
 
-        // Compares two values of the same unmanaged type by underlying memory
-        // Ignoring any overridden value checks
-        // Size is fixed
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        private static unsafe bool ValueEquals(ref T a, ref T b)
-        {
-            // get unmanaged pointers
-            var aptr = UnsafeUtility.AddressOf(ref a);
-            var bptr = UnsafeUtility.AddressOf(ref b);
-
-            // compare addresses
-            return UnsafeUtility.MemCmp(aptr, bptr, sizeof(T)) == 0;
-        }
-
         /// <summary>
         /// Sets the <see cref="Value"/>, marks the <see cref="NetworkVariable{T}"/> dirty, and invokes the <see cref="OnValueChanged"/> callback
         /// if there are subscribers to that event.
@@ -87,7 +71,7 @@ namespace Unity.Netcode
         /// <param name="value">the new value of type `T` to be set/></param>
         private protected void Set(T value)
         {
-            m_IsDirty = true;
+            SetDirty(true);
             T previousValue = m_InternalValue;
             m_InternalValue = value;
             OnValueChanged?.Invoke(previousValue, m_InternalValue);
@@ -115,11 +99,11 @@ namespace Unity.Netcode
             // would be stored in different fields
 
             T previousValue = m_InternalValue;
-            NetworkVariableSerialization<T>.Read(reader, out m_InternalValue);
+            NetworkVariableSerialization<T>.Read(reader, ref m_InternalValue);
 
             if (keepDirtyDelta)
             {
-                m_IsDirty = true;
+                SetDirty(true);
             }
 
             OnValueChanged?.Invoke(previousValue, m_InternalValue);
@@ -128,7 +112,7 @@ namespace Unity.Netcode
         /// <inheritdoc />
         public override void ReadField(FastBufferReader reader)
         {
-            NetworkVariableSerialization<T>.Read(reader, out m_InternalValue);
+            NetworkVariableSerialization<T>.Read(reader, ref m_InternalValue);
         }
 
         /// <inheritdoc />

Runtime/NetworkVariable/NetworkVariableBase.cs

@@ -1,4 +1,5 @@
 using System;
+using UnityEngine;
 
 namespace Unity.Netcode
 {
@@ -54,7 +55,7 @@ namespace Unity.Netcode
         /// The <see cref="m_IsDirty"/> property is used to determine if the
         /// value of the `NetworkVariable` has changed.
         /// </summary>
-        private protected bool m_IsDirty;
+        private bool m_IsDirty;
 
         /// <summary>
         /// Gets or sets the name of the network variable's instance
@@ -79,6 +80,17 @@ namespace Unity.Netcode
         public virtual void SetDirty(bool isDirty)
         {
             m_IsDirty = isDirty;
+
+            if (m_IsDirty)
+            {
+                if (m_NetworkBehaviour == null)
+                {
+                    Debug.LogWarning($"NetworkVariable is written to, but doesn't know its NetworkBehaviour yet. " +
+                                     "Are you modifying a NetworkVariable before the NetworkObject is spawned?");
+                    return;
+                }
+                m_NetworkBehaviour.NetworkManager.MarkNetworkObjectDirty(m_NetworkBehaviour.NetworkObject);
+            }
         }
 
         /// <summary>
@@ -111,7 +123,7 @@ namespace Unity.Netcode
                 case NetworkVariableReadPermission.Everyone:
                     return true;
                 case NetworkVariableReadPermission.Owner:
-                    return clientId == m_NetworkBehaviour.NetworkObject.OwnerClientId;
+                    return clientId == m_NetworkBehaviour.NetworkObject.OwnerClientId || NetworkManager.ServerClientId == clientId;
             }
         }
 

Runtime/NetworkVariable/NetworkVariableSerialization.cs

@@ -1,7 +1,6 @@
 using System;
-using System.Collections.Generic;
 using Unity.Collections;
-using UnityEngine;
+using Unity.Collections.LowLevel.Unsafe;
 
 namespace Unity.Netcode
 {
@@ -18,7 +17,7 @@ namespace Unity.Netcode
         // Taking T as an in parameter like we do in other places would require making a copy
         // of it to pass it as a ref parameter.
         public void Write(FastBufferWriter writer, ref T value);
-        public void Read(FastBufferReader reader, out T value);
+        public void Read(FastBufferReader reader, ref T value);
     }
 
     /// <summary>
@@ -35,79 +34,80 @@ namespace Unity.Netcode
         {
             writer.WriteUnmanagedSafe(value);
         }
-        public void Read(FastBufferReader reader, out T value)
+        public void Read(FastBufferReader reader, ref T value)
         {
             reader.ReadUnmanagedSafe(out value);
         }
     }
 
     /// <summary>
-    /// Serializer for FixedStrings, which does the same thing FastBufferWriter/FastBufferReader do,
-    /// but is implemented to get the data it needs using open instance delegates that are passed in
-    /// via reflection. This prevents needing T to meet any interface requirements (which isn't achievable
-    /// without incurring GC allocs on every call to Write or Read - reflection + Open Instance Delegates
-    /// circumvent that.)
-    ///
-    /// Tests show that calling these delegates doesn't cause any GC allocations even though they're
-    /// obtained via reflection and Delegate.CreateDelegate() and called on types that, at compile time,
-    /// aren't known to actually contain those methods.
+    /// Serializer for FixedStrings
     /// </summary>
     /// <typeparam name="T"></typeparam>
-    internal class FixedStringSerializer<T> : INetworkVariableSerializer<T> where T : unmanaged
+    internal class FixedStringSerializer<T> : INetworkVariableSerializer<T> where T : unmanaged, INativeList<byte>, IUTF8Bytes
     {
-        internal delegate int GetLengthDelegate(ref T value);
-        internal delegate void SetLengthDelegate(ref T value, int length);
-        internal unsafe delegate byte* GetUnsafePtrDelegate(ref T value);
-
-        internal GetLengthDelegate GetLength;
-        internal SetLengthDelegate SetLength;
-        internal GetUnsafePtrDelegate GetUnsafePtr;
-
-        public unsafe void Write(FastBufferWriter writer, ref T value)
+        public void Write(FastBufferWriter writer, ref T value)
         {
-            int length = GetLength(ref value);
-            byte* data = GetUnsafePtr(ref value);
-            writer.WriteUnmanagedSafe(length);
-            writer.WriteBytesSafe(data, length);
+            writer.WriteValueSafe(value);
         }
-        public unsafe void Read(FastBufferReader reader, out T value)
+        public void Read(FastBufferReader reader, ref T value)
         {
-            value = new T();
-            reader.ReadValueSafe(out int length);
-            SetLength(ref value, length);
-            reader.ReadBytesSafe(GetUnsafePtr(ref value), length);
+            reader.ReadValueSafeInPlace(ref value);
         }
     }
 
     /// <summary>
-    /// Serializer for INetworkSerializable types, which does the same thing
-    /// FastBufferWriter/FastBufferReader do, but is implemented to call the NetworkSerialize() method
-    /// via open instance delegates passed in via reflection. This prevents needing T to meet any interface
-    /// requirements (which isn't achievable without incurring GC allocs on every call to Write or Read -
-    /// reflection + Open Instance Delegates circumvent that.)
-    ///
-    /// Tests show that calling these delegates doesn't cause any GC allocations even though they're
-    /// obtained via reflection and Delegate.CreateDelegate() and called on types that, at compile time,
-    /// aren't known to actually contain those methods.
+    /// Serializer for unmanaged INetworkSerializable types
     /// </summary>
     /// <typeparam name="T"></typeparam>
-    internal class NetworkSerializableSerializer<T> : INetworkVariableSerializer<T> where T : unmanaged
+    internal class UnmanagedNetworkSerializableSerializer<T> : INetworkVariableSerializer<T> where T : unmanaged, INetworkSerializable
     {
-        internal delegate void WriteValueDelegate(ref T value, BufferSerializer<BufferSerializerWriter> serializer);
-        internal delegate void ReadValueDelegate(ref T value, BufferSerializer<BufferSerializerReader> serializer);
-
-        internal WriteValueDelegate WriteValue;
-        internal ReadValueDelegate ReadValue;
         public void Write(FastBufferWriter writer, ref T value)
         {
             var bufferSerializer = new BufferSerializer<BufferSerializerWriter>(new BufferSerializerWriter(writer));
-            WriteValue(ref value, bufferSerializer);
+            value.NetworkSerialize(bufferSerializer);
         }
-        public void Read(FastBufferReader reader, out T value)
+        public void Read(FastBufferReader reader, ref T value)
         {
-            value = new T();
             var bufferSerializer = new BufferSerializer<BufferSerializerReader>(new BufferSerializerReader(reader));
-            ReadValue(ref value, bufferSerializer);
+            value.NetworkSerialize(bufferSerializer);
+
+        }
+    }
+
+    /// <summary>
+    /// Serializer for managed INetworkSerializable types, which differs from the unmanaged implementation in that it
+    /// has to be null-aware
+    /// <typeparam name="T"></typeparam>
+    internal class ManagedNetworkSerializableSerializer<T> : INetworkVariableSerializer<T> where T : class, INetworkSerializable, new()
+    {
+        public void Write(FastBufferWriter writer, ref T value)
+        {
+            var bufferSerializer = new BufferSerializer<BufferSerializerWriter>(new BufferSerializerWriter(writer));
+            bool isNull = (value == null);
+            bufferSerializer.SerializeValue(ref isNull);
+            if (!isNull)
+            {
+                value.NetworkSerialize(bufferSerializer);
+            }
+        }
+        public void Read(FastBufferReader reader, ref T value)
+        {
+            var bufferSerializer = new BufferSerializer<BufferSerializerReader>(new BufferSerializerReader(reader));
+            bool isNull = false;
+            bufferSerializer.SerializeValue(ref isNull);
+            if (isNull)
+            {
+                value = null;
+            }
+            else
+            {
+                if (value == null)
+                {
+                    value = new T();
+                }
+                value.NetworkSerialize(bufferSerializer);
+            }
         }
     }
 
@@ -164,7 +164,7 @@ namespace Unity.Netcode
             }
             UserNetworkVariableSerialization<T>.WriteValue(writer, value);
         }
-        public void Read(FastBufferReader reader, out T value)
+        public void Read(FastBufferReader reader, ref T value)
         {
             if (UserNetworkVariableSerialization<T>.ReadValue == null || UserNetworkVariableSerialization<T>.WriteValue == null)
             {
@@ -174,34 +174,95 @@ namespace Unity.Netcode
         }
     }
 
-    internal static class NetworkVariableSerializationTypes
+    /// <summary>
+    /// This class contains initialization functions for various different types used in NetworkVariables.
+    /// Generally speaking, these methods are called by a module initializer created by codegen (NetworkBehaviourILPP)
+    /// and do not need to be called manually.
+    ///
+    /// There are two types of initializers: Serializers and EqualityCheckers. Every type must have an EqualityChecker
+    /// registered to it in order to be used in NetworkVariable; however, not all types need a Serializer. Types without
+    /// a serializer registered will fall back to using the delegates in <see cref="UserNetworkVariableSerialization{T}"/>.
+    /// If no such delegate has been registered, a type without a serializer will throw an exception on the first attempt
+    /// to serialize or deserialize it. (Again, however, codegen handles this automatically and this registration doesn't
+    /// typically need to be performed manually.)
+    /// </summary>
+    public static class NetworkVariableSerializationTypes
     {
-        internal static readonly HashSet<Type> BaseSupportedTypes = new HashSet<Type>
+        /// <summary>
+        /// Registeres an unmanaged type that will be serialized by a direct memcpy into a buffer
+        /// </summary>
+        /// <typeparam name="T"></typeparam>
+        public static void InitializeSerializer_UnmanagedByMemcpy<T>() where T : unmanaged
         {
-            typeof(bool),
-            typeof(byte),
-            typeof(sbyte),
-            typeof(char),
-            typeof(decimal),
-            typeof(double),
-            typeof(float),
-            typeof(int),
-            typeof(uint),
-            typeof(long),
-            typeof(ulong),
-            typeof(short),
-            typeof(ushort),
-            typeof(Vector2),
-            typeof(Vector3),
-            typeof(Vector2Int),
-            typeof(Vector3Int),
-            typeof(Vector4),
-            typeof(Quaternion),
-            typeof(Color),
-            typeof(Color32),
-            typeof(Ray),
-            typeof(Ray2D)
-        };
+            NetworkVariableSerialization<T>.Serializer = new UnmanagedTypeSerializer<T>();
+        }
+
+        /// <summary>
+        /// Registers an unmanaged type that implements INetworkSerializable and will be serialized through a call to
+        /// NetworkSerialize
+        /// </summary>
+        /// <typeparam name="T"></typeparam>
+        public static void InitializeSerializer_UnmanagedINetworkSerializable<T>() where T : unmanaged, INetworkSerializable
+        {
+            NetworkVariableSerialization<T>.Serializer = new UnmanagedNetworkSerializableSerializer<T>();
+        }
+
+        /// <summary>
+        /// Registers a managed type that implements INetworkSerializable and will be serialized through a call to
+        /// NetworkSerialize
+        /// </summary>
+        /// <typeparam name="T"></typeparam>
+        public static void InitializeSerializer_ManagedINetworkSerializable<T>() where T : class, INetworkSerializable, new()
+        {
+            NetworkVariableSerialization<T>.Serializer = new ManagedNetworkSerializableSerializer<T>();
+        }
+
+        /// <summary>
+        /// Registers a FixedString type that will be serialized through FastBufferReader/FastBufferWriter's FixedString
+        /// serializers
+        /// </summary>
+        /// <typeparam name="T"></typeparam>
+        public static void InitializeSerializer_FixedString<T>() where T : unmanaged, INativeList<byte>, IUTF8Bytes
+        {
+            NetworkVariableSerialization<T>.Serializer = new FixedStringSerializer<T>();
+        }
+
+        /// <summary>
+        /// Registers a managed type that will be checked for equality using T.Equals()
+        /// </summary>
+        /// <typeparam name="T"></typeparam>
+        public static void InitializeEqualityChecker_ManagedIEquatable<T>() where T : class, IEquatable<T>
+        {
+            NetworkVariableSerialization<T>.AreEqual = NetworkVariableSerialization<T>.EqualityEqualsObject;
+        }
+
+        /// <summary>
+        /// Registers an unmanaged type that will be checked for equality using T.Equals()
+        /// </summary>
+        /// <typeparam name="T"></typeparam>
+        public static void InitializeEqualityChecker_UnmanagedIEquatable<T>() where T : unmanaged, IEquatable<T>
+        {
+            NetworkVariableSerialization<T>.AreEqual = NetworkVariableSerialization<T>.EqualityEquals;
+        }
+
+        /// <summary>
+        /// Registers an unmanaged type that will be checked for equality using memcmp and only considered
+        /// equal if they are bitwise equivalent in memory
+        /// </summary>
+        /// <typeparam name="T"></typeparam>
+        public static void InitializeEqualityChecker_UnmanagedValueEquals<T>() where T : unmanaged
+        {
+            NetworkVariableSerialization<T>.AreEqual = NetworkVariableSerialization<T>.ValueEquals;
+        }
+
+        /// <summary>
+        /// Registers a managed type that will be checked for equality using the == operator
+        /// </summary>
+        /// <typeparam name="T"></typeparam>
+        public static void InitializeEqualityChecker_ManagedClassEquals<T>() where T : class
+        {
+            NetworkVariableSerialization<T>.AreEqual = NetworkVariableSerialization<T>.ClassEquals;
+        }
     }
 
     /// <summary>
@@ -212,56 +273,59 @@ namespace Unity.Netcode
     /// </summary>
     /// <typeparam name="T">The type the associated NetworkVariable is templated on</typeparam>
     [Serializable]
-    public static class NetworkVariableSerialization<T> where T : unmanaged
+    public static class NetworkVariableSerialization<T>
     {
-        private static INetworkVariableSerializer<T> s_Serializer = GetSerializer();
+        internal static INetworkVariableSerializer<T> Serializer = new FallbackSerializer<T>();
 
-        private static INetworkVariableSerializer<T> GetSerializer()
+        internal delegate bool EqualsDelegate(ref T a, ref T b);
+        internal static EqualsDelegate AreEqual;
+
+        // Compares two values of the same unmanaged type by underlying memory
+        // Ignoring any overridden value checks
+        // Size is fixed
+        internal static unsafe bool ValueEquals<TValueType>(ref TValueType a, ref TValueType b) where TValueType : unmanaged
         {
-            if (NetworkVariableSerializationTypes.BaseSupportedTypes.Contains(typeof(T)))
+            // get unmanaged pointers
+            var aptr = UnsafeUtility.AddressOf(ref a);
+            var bptr = UnsafeUtility.AddressOf(ref b);
+
+            // compare addresses
+            return UnsafeUtility.MemCmp(aptr, bptr, sizeof(TValueType)) == 0;
+        }
+
+        internal static bool EqualityEqualsObject<TValueType>(ref TValueType a, ref TValueType b) where TValueType : class, IEquatable<TValueType>
+        {
+            if (a == null)
             {
-                return new UnmanagedTypeSerializer<T>();
-            }
-            if (typeof(INetworkSerializeByMemcpy).IsAssignableFrom(typeof(T)))
-            {
-                return new UnmanagedTypeSerializer<T>();
-            }
-            if (typeof(Enum).IsAssignableFrom(typeof(T)))
-            {
-                return new UnmanagedTypeSerializer<T>();
+                return b == null;
             }
 
-            if (typeof(INetworkSerializable).IsAssignableFrom(typeof(T)))
+            if (b == null)
             {
-                // Obtains "Open Instance Delegates" for the type's NetworkSerialize() methods -
-                // one for an instance of the generic method taking BufferSerializerWriter as T,
-                // one for an instance of the generic method taking BufferSerializerReader as T
-                var writeMethod = (NetworkSerializableSerializer<T>.WriteValueDelegate)Delegate.CreateDelegate(typeof(NetworkSerializableSerializer<T>.WriteValueDelegate), null, typeof(T).GetMethod(nameof(INetworkSerializable.NetworkSerialize)).MakeGenericMethod(typeof(BufferSerializerWriter)));
-                var readMethod = (NetworkSerializableSerializer<T>.ReadValueDelegate)Delegate.CreateDelegate(typeof(NetworkSerializableSerializer<T>.ReadValueDelegate), null, typeof(T).GetMethod(nameof(INetworkSerializable.NetworkSerialize)).MakeGenericMethod(typeof(BufferSerializerReader)));
-                return new NetworkSerializableSerializer<T> { WriteValue = writeMethod, ReadValue = readMethod };
+                return false;
             }
 
-            if (typeof(IUTF8Bytes).IsAssignableFrom(typeof(T)) && typeof(INativeList<byte>).IsAssignableFrom(typeof(T)))
-            {
-                // Get "OpenInstanceDelegates" for the Length property (get and set, which are prefixed
-                // with "get_" and "set_" under the hood and emitted as methods) and GetUnsafePtr()
-                var getLength = (FixedStringSerializer<T>.GetLengthDelegate)Delegate.CreateDelegate(typeof(FixedStringSerializer<T>.GetLengthDelegate), null, typeof(T).GetMethod("get_" + nameof(INativeList<byte>.Length)));
-                var setLength = (FixedStringSerializer<T>.SetLengthDelegate)Delegate.CreateDelegate(typeof(FixedStringSerializer<T>.SetLengthDelegate), null, typeof(T).GetMethod("set_" + nameof(INativeList<byte>.Length)));
-                var getUnsafePtr = (FixedStringSerializer<T>.GetUnsafePtrDelegate)Delegate.CreateDelegate(typeof(FixedStringSerializer<T>.GetUnsafePtrDelegate), null, typeof(T).GetMethod(nameof(IUTF8Bytes.GetUnsafePtr)));
-                return new FixedStringSerializer<T> { GetLength = getLength, SetLength = setLength, GetUnsafePtr = getUnsafePtr };
-            }
+            return a.Equals(b);
+        }
 
-            return new FallbackSerializer<T>();
+        internal static bool EqualityEquals<TValueType>(ref TValueType a, ref TValueType b) where TValueType : unmanaged, IEquatable<TValueType>
+        {
+            return a.Equals(b);
+        }
+
+        internal static bool ClassEquals<TValueType>(ref TValueType a, ref TValueType b) where TValueType : class
+        {
+            return a == b;
         }
 
         internal static void Write(FastBufferWriter writer, ref T value)
         {
-            s_Serializer.Write(writer, ref value);
+            Serializer.Write(writer, ref value);
         }
 
-        internal static void Read(FastBufferReader reader, out T value)
+        internal static void Read(FastBufferReader reader, ref T value)
         {
-            s_Serializer.Read(reader, out value);
+            Serializer.Read(reader, ref value);
         }
     }
 }

Runtime/SceneManagement/ISceneManagerHandler.cs

@@ -1,4 +1,3 @@
-using System;
 using UnityEngine;
 using UnityEngine.SceneManagement;
 
@@ -10,25 +9,8 @@ namespace Unity.Netcode
     /// </summary>
     internal interface ISceneManagerHandler
     {
-        // Generic action to call when a scene is finished loading/unloading
-        struct SceneEventAction
-        {
-            internal uint SceneEventId;
-            internal Action<uint> EventAction;
-            /// <summary>
-            /// Used server-side for integration testing in order to
-            /// invoke the SceneEventProgress once done loading
-            /// </summary>
-            internal Action Completed;
-            internal void Invoke()
-            {
-                Completed?.Invoke();
-                EventAction.Invoke(SceneEventId);
-            }
-        }
+        AsyncOperation LoadSceneAsync(string sceneName, LoadSceneMode loadSceneMode, SceneEventProgress sceneEventProgress);
 
-        AsyncOperation LoadSceneAsync(string sceneName, LoadSceneMode loadSceneMode, SceneEventAction sceneEventAction);
-
-        AsyncOperation UnloadSceneAsync(Scene scene, SceneEventAction sceneEventAction);
+        AsyncOperation UnloadSceneAsync(Scene scene, SceneEventProgress sceneEventProgress);
     }
 }

Runtime/SceneManagement/NetworkSceneManager.cs

@@ -338,17 +338,17 @@ namespace Unity.Netcode
         /// </summary>
         private class DefaultSceneManagerHandler : ISceneManagerHandler
         {
-            public AsyncOperation LoadSceneAsync(string sceneName, LoadSceneMode loadSceneMode, ISceneManagerHandler.SceneEventAction sceneEventAction)
+            public AsyncOperation LoadSceneAsync(string sceneName, LoadSceneMode loadSceneMode, SceneEventProgress sceneEventProgress)
             {
                 var operation = SceneManager.LoadSceneAsync(sceneName, loadSceneMode);
-                operation.completed += new Action<AsyncOperation>(asyncOp2 => { sceneEventAction.Invoke(); });
+                sceneEventProgress.SetAsyncOperation(operation);
                 return operation;
             }
 
-            public AsyncOperation UnloadSceneAsync(Scene scene, ISceneManagerHandler.SceneEventAction sceneEventAction)
+            public AsyncOperation UnloadSceneAsync(Scene scene, SceneEventProgress sceneEventProgress)
             {
                 var operation = SceneManager.UnloadSceneAsync(scene);
-                operation.completed += new Action<AsyncOperation>(asyncOp2 => { sceneEventAction.Invoke(); });
+                sceneEventProgress.SetAsyncOperation(operation);
                 return operation;
             }
         }
@@ -887,12 +887,14 @@ namespace Unity.Netcode
         private bool OnSceneEventProgressCompleted(SceneEventProgress sceneEventProgress)
         {
             var sceneEventData = BeginSceneEvent();
+            var clientsThatCompleted = sceneEventProgress.GetClientsWithStatus(true);
+            var clientsThatTimedOut = sceneEventProgress.GetClientsWithStatus(false);
             sceneEventData.SceneEventProgressId = sceneEventProgress.Guid;
             sceneEventData.SceneHash = sceneEventProgress.SceneHash;
             sceneEventData.SceneEventType = sceneEventProgress.SceneEventType;
-            sceneEventData.ClientsCompleted = sceneEventProgress.DoneClients;
+            sceneEventData.ClientsCompleted = clientsThatCompleted;
             sceneEventData.LoadSceneMode = sceneEventProgress.LoadSceneMode;
-            sceneEventData.ClientsTimedOut = sceneEventProgress.ClientsThatStartedSceneEvent.Except(sceneEventProgress.DoneClients).ToList();
+            sceneEventData.ClientsTimedOut = clientsThatTimedOut;
 
             var message = new SceneEventMessage
             {
@@ -913,8 +915,8 @@ namespace Unity.Netcode
                 SceneName = SceneNameFromHash(sceneEventProgress.SceneHash),
                 ClientId = NetworkManager.ServerClientId,
                 LoadSceneMode = sceneEventProgress.LoadSceneMode,
-                ClientsThatCompleted = sceneEventProgress.DoneClients,
-                ClientsThatTimedOut = m_NetworkManager.ConnectedClients.Keys.Except(sceneEventProgress.DoneClients).ToList(),
+                ClientsThatCompleted = clientsThatCompleted,
+                ClientsThatTimedOut = clientsThatTimedOut,
             });
 
             if (sceneEventData.SceneEventType == SceneEventType.LoadEventCompleted)
@@ -969,18 +971,9 @@ namespace Unity.Netcode
             sceneEventProgress.SceneEventType = SceneEventType.UnloadEventCompleted;
 
             ScenesLoaded.Remove(scene.handle);
-            var sceneEventAction = new ISceneManagerHandler.SceneEventAction() { SceneEventId = sceneEventData.SceneEventId, EventAction = OnSceneUnloaded };
-            var sceneUnload = SceneManagerHandler.UnloadSceneAsync(scene, sceneEventAction);
-
-            // If integration testing, IntegrationTestSceneHandler returns null
-            if (sceneUnload == null)
-            {
-                sceneEventProgress.SetSceneLoadOperation(sceneEventAction);
-            }
-            else
-            {
-                sceneEventProgress.SetSceneLoadOperation(sceneUnload);
-            }
+            sceneEventProgress.SceneEventId = sceneEventData.SceneEventId;
+            sceneEventProgress.OnSceneEventCompleted = OnSceneUnloaded;
+            var sceneUnload = SceneManagerHandler.UnloadSceneAsync(scene, sceneEventProgress);
 
             // Notify local server that a scene is going to be unloaded
             OnSceneEvent?.Invoke(new SceneEvent()
@@ -1024,9 +1017,10 @@ namespace Unity.Netcode
                     $"because the client scene handle {sceneHandle} was not found in ScenesLoaded!");
             }
             m_IsSceneEventActive = true;
-
-            var sceneUnload = SceneManagerHandler.UnloadSceneAsync(ScenesLoaded[sceneHandle],
-                new ISceneManagerHandler.SceneEventAction() { SceneEventId = sceneEventData.SceneEventId, EventAction = OnSceneUnloaded });
+            var sceneEventProgress = new SceneEventProgress(m_NetworkManager);
+            sceneEventProgress.SceneEventId = sceneEventData.SceneEventId;
+            sceneEventProgress.OnSceneEventCompleted = OnSceneUnloaded;
+            var sceneUnload = SceneManagerHandler.UnloadSceneAsync(ScenesLoaded[sceneHandle], sceneEventProgress);
 
             ScenesLoaded.Remove(sceneHandle);
 
@@ -1070,7 +1064,7 @@ namespace Unity.Netcode
                 //Only if we are a host do we want register having loaded for the associated SceneEventProgress
                 if (SceneEventProgressTracking.ContainsKey(sceneEventData.SceneEventProgressId) && m_NetworkManager.IsHost)
                 {
-                    SceneEventProgressTracking[sceneEventData.SceneEventProgressId].AddClientAsDone(NetworkManager.ServerClientId);
+                    SceneEventProgressTracking[sceneEventData.SceneEventProgressId].ClientFinishedSceneEvent(NetworkManager.ServerClientId);
                 }
             }
 
@@ -1119,8 +1113,10 @@ namespace Unity.Netcode
                 // Validate the scene as well as ignore the DDOL (which will have a negative buildIndex)
                 if (currentActiveScene.name != keyHandleEntry.Value.name && keyHandleEntry.Value.buildIndex >= 0)
                 {
-                    var sceneUnload = SceneManagerHandler.UnloadSceneAsync(keyHandleEntry.Value,
-                        new ISceneManagerHandler.SceneEventAction() { SceneEventId = sceneEventId, EventAction = EmptySceneUnloadedOperation });
+                    var sceneEventProgress = new SceneEventProgress(m_NetworkManager);
+                    sceneEventProgress.SceneEventId = sceneEventId;
+                    sceneEventProgress.OnSceneEventCompleted = EmptySceneUnloadedOperation;
+                    var sceneUnload = SceneManagerHandler.UnloadSceneAsync(keyHandleEntry.Value, sceneEventProgress);
                     SceneUnloadEventHandler.RegisterScene(this, keyHandleEntry.Value, LoadSceneMode.Additive, sceneUnload);
                 }
             }
@@ -1180,18 +1176,9 @@ namespace Unity.Netcode
             }
 
             // Now start loading the scene
-            var sceneEventAction = new ISceneManagerHandler.SceneEventAction() { SceneEventId = sceneEventId, EventAction = OnSceneLoaded };
-            var sceneLoad = SceneManagerHandler.LoadSceneAsync(sceneName, loadSceneMode, sceneEventAction);
-            // If integration testing, IntegrationTestSceneHandler returns null
-            if (sceneLoad == null)
-            {
-                sceneEventProgress.SetSceneLoadOperation(sceneEventAction);
-            }
-            else
-            {
-                sceneEventProgress.SetSceneLoadOperation(sceneLoad);
-            }
-
+            sceneEventProgress.SceneEventId = sceneEventId;
+            sceneEventProgress.OnSceneEventCompleted = OnSceneLoaded;
+            var sceneLoad = SceneManagerHandler.LoadSceneAsync(sceneName, loadSceneMode, sceneEventProgress);
             // Notify the local server that a scene loading event has begun
             OnSceneEvent?.Invoke(new SceneEvent()
             {
@@ -1355,9 +1342,10 @@ namespace Unity.Netcode
                 SceneUnloadEventHandler.RegisterScene(this, SceneManager.GetActiveScene(), LoadSceneMode.Single);
 
             }
-
-            var sceneLoad = SceneManagerHandler.LoadSceneAsync(sceneName, sceneEventData.LoadSceneMode,
-                new ISceneManagerHandler.SceneEventAction() { SceneEventId = sceneEventId, EventAction = OnSceneLoaded });
+            var sceneEventProgress = new SceneEventProgress(m_NetworkManager);
+            sceneEventProgress.SceneEventId = sceneEventId;
+            sceneEventProgress.OnSceneEventCompleted = OnSceneLoaded;
+            var sceneLoad = SceneManagerHandler.LoadSceneAsync(sceneName, sceneEventData.LoadSceneMode, sceneEventProgress);
 
             OnSceneEvent?.Invoke(new SceneEvent()
             {
@@ -1453,6 +1441,9 @@ namespace Unity.Netcode
                 }
             }
 
+            // Add any despawned when spawned in-scene placed NetworkObjects to the scene event data
+            sceneEventData.AddDespawnedInSceneNetworkObjects();
+
             // Set the server's scene's handle so the client can build a look up table
             sceneEventData.SceneHandle = scene.handle;
 
@@ -1488,7 +1479,7 @@ namespace Unity.Netcode
             //Second, only if we are a host do we want register having loaded for the associated SceneEventProgress
             if (SceneEventProgressTracking.ContainsKey(sceneEventData.SceneEventProgressId) && m_NetworkManager.IsHost)
             {
-                SceneEventProgressTracking[sceneEventData.SceneEventProgressId].AddClientAsDone(NetworkManager.ServerClientId);
+                SceneEventProgressTracking[sceneEventData.SceneEventProgressId].ClientFinishedSceneEvent(NetworkManager.ServerClientId);
             }
             EndSceneEvent(sceneEventId);
         }
@@ -1662,8 +1653,10 @@ namespace Unity.Netcode
             if (!shouldPassThrough)
             {
                 // If not, then load the scene
-                sceneLoad = SceneManagerHandler.LoadSceneAsync(sceneName, loadSceneMode,
-                new ISceneManagerHandler.SceneEventAction() { SceneEventId = sceneEventId, EventAction = ClientLoadedSynchronization });
+                var sceneEventProgress = new SceneEventProgress(m_NetworkManager);
+                sceneEventProgress.SceneEventId = sceneEventId;
+                sceneEventProgress.OnSceneEventCompleted = ClientLoadedSynchronization;
+                sceneLoad = SceneManagerHandler.LoadSceneAsync(sceneName, loadSceneMode, sceneEventProgress);
 
                 // Notify local client that a scene load has begun
                 OnSceneEvent?.Invoke(new SceneEvent()
@@ -1880,7 +1873,7 @@ namespace Unity.Netcode
 
                         if (SceneEventProgressTracking.ContainsKey(sceneEventData.SceneEventProgressId))
                         {
-                            SceneEventProgressTracking[sceneEventData.SceneEventProgressId].AddClientAsDone(clientId);
+                            SceneEventProgressTracking[sceneEventData.SceneEventProgressId].ClientFinishedSceneEvent(clientId);
                         }
                         EndSceneEvent(sceneEventId);
                         break;
@@ -1889,7 +1882,7 @@ namespace Unity.Netcode
                     {
                         if (SceneEventProgressTracking.ContainsKey(sceneEventData.SceneEventProgressId))
                         {
-                            SceneEventProgressTracking[sceneEventData.SceneEventProgressId].AddClientAsDone(clientId);
+                            SceneEventProgressTracking[sceneEventData.SceneEventProgressId].ClientFinishedSceneEvent(clientId);
                         }
                         // Notify the local server that the client has finished unloading a scene
                         OnSceneEvent?.Invoke(new SceneEvent()

Runtime/SceneManagement/SceneEventData.cs

@@ -243,13 +243,33 @@ namespace Unity.Netcode
                     m_NetworkObjectsSync.Add(sobj);
                 }
             }
+
+            // Sort by parents before children
+            m_NetworkObjectsSync.Sort(SortParentedNetworkObjects);
+
+            // Sort by INetworkPrefabInstanceHandler implementation before the
+            // NetworkObjects spawned by the implementation
             m_NetworkObjectsSync.Sort(SortNetworkObjects);
+
+            // This is useful to know what NetworkObjects a client is going to be synchronized with
+            // as well as the order in which they will be deserialized
+            if (m_NetworkManager.LogLevel == LogLevel.Developer)
+            {
+                var messageBuilder = new System.Text.StringBuilder(0xFFFF);
+                messageBuilder.Append("[Server-Side Client-Synchronization] NetworkObject serialization order:");
+                foreach (var networkObject in m_NetworkObjectsSync)
+                {
+                    messageBuilder.Append($"{networkObject.name}");
+                }
+                NetworkLog.LogInfo(messageBuilder.ToString());
+            }
         }
 
         internal void AddDespawnedInSceneNetworkObjects()
         {
             m_DespawnedInSceneObjectsSync.Clear();
-            var inSceneNetworkObjects = UnityEngine.Object.FindObjectsOfType<NetworkObject>().Where((c) => c.NetworkManager == m_NetworkManager);
+            // Find all active and non-active in-scene placed NetworkObjects
+            var inSceneNetworkObjects = UnityEngine.Object.FindObjectsOfType<NetworkObject>(includeInactive: true).Where((c) => c.NetworkManager == m_NetworkManager);
             foreach (var sobj in inSceneNetworkObjects)
             {
                 if (sobj.IsSceneObject.HasValue && sobj.IsSceneObject.Value && !sobj.IsSpawned)
@@ -323,6 +343,32 @@ namespace Unity.Netcode
             return 0;
         }
 
+        /// <summary>
+        /// Sorts the synchronization order of the NetworkObjects to be serialized
+        /// by parents before children.
+        /// </summary>
+        /// <remarks>
+        /// This only handles late joining players. Spawning and nesting several children
+        /// dynamically is still handled by the orphaned child list when deserialized out of
+        /// hierarchical order (i.e. Spawn parent and child dynamically, parent message is
+        /// dropped and re-sent but child object is received and processed)
+        /// </remarks>
+        private int SortParentedNetworkObjects(NetworkObject first, NetworkObject second)
+        {
+            // If the first has a parent, move the first down
+            if (first.transform.parent != null)
+            {
+                return 1;
+            }
+            else // If the second has a parent and the first does not, then move the first up
+            if (second.transform.parent != null)
+            {
+                return -1;
+            }
+            return 0;
+        }
+
+
         /// <summary>
         /// Client and Server Side:
         /// Serializes data based on the SceneEvent type (<see cref="SceneEventType"/>)
@@ -398,9 +444,9 @@ namespace Unity.Netcode
             int totalBytes = 0;
 
             // Write the number of NetworkObjects we are serializing
-            BytePacker.WriteValuePacked(writer, m_NetworkObjectsSync.Count());
+            BytePacker.WriteValuePacked(writer, m_NetworkObjectsSync.Count);
             // Serialize all NetworkObjects that are spawned
-            for (var i = 0; i < m_NetworkObjectsSync.Count(); ++i)
+            for (var i = 0; i < m_NetworkObjectsSync.Count; ++i)
             {
                 var noStart = writer.Position;
                 var sceneObject = m_NetworkObjectsSync[i].GetMessageSceneObject(TargetClientId);
@@ -411,12 +457,11 @@ namespace Unity.Netcode
             }
 
             // Write the number of despawned in-scene placed NetworkObjects
-            writer.WriteValueSafe(m_DespawnedInSceneObjectsSync.Count());
+            writer.WriteValueSafe(m_DespawnedInSceneObjectsSync.Count);
             // Write the scene handle and GlobalObjectIdHash value
-            for (var i = 0; i < m_DespawnedInSceneObjectsSync.Count(); ++i)
+            for (var i = 0; i < m_DespawnedInSceneObjectsSync.Count; ++i)
             {
                 var noStart = writer.Position;
-                var sceneObject = m_DespawnedInSceneObjectsSync[i].GetMessageSceneObject(TargetClientId);
                 BytePacker.WriteValuePacked(writer, m_DespawnedInSceneObjectsSync[i].GetSceneOriginHandle());
                 BytePacker.WriteValuePacked(writer, m_DespawnedInSceneObjectsSync[i].GlobalObjectIdHash);
                 var noStop = writer.Position;
@@ -462,6 +507,15 @@ namespace Unity.Netcode
                 }
             }
 
+            // Write the number of despawned in-scene placed NetworkObjects
+            writer.WriteValueSafe(m_DespawnedInSceneObjectsSync.Count);
+            // Write the scene handle and GlobalObjectIdHash value
+            for (var i = 0; i < m_DespawnedInSceneObjectsSync.Count; ++i)
+            {
+                BytePacker.WriteValuePacked(writer, m_DespawnedInSceneObjectsSync[i].GetSceneOriginHandle());
+                BytePacker.WriteValuePacked(writer, m_DespawnedInSceneObjectsSync[i].GlobalObjectIdHash);
+            }
+
             var tailPosition = writer.Position;
             // Reposition to our count position to the head before we wrote our object count
             writer.Seek(headPosition);
@@ -579,6 +633,8 @@ namespace Unity.Netcode
                     sceneObject.Deserialize(InternalBuffer);
                     NetworkObject.AddSceneObject(sceneObject, InternalBuffer, m_NetworkManager);
                 }
+                // Now deserialize the despawned in-scene placed NetworkObjects list (if any)
+                DeserializeDespawnedInScenePlacedNetworkObjects();
             }
             finally
             {
@@ -701,6 +757,84 @@ namespace Unity.Netcode
             }
         }
 
+        /// <summary>
+        /// For synchronizing any despawned in-scene placed NetworkObjects that were
+        /// despawned by the server during synchronization or scene loading
+        /// </summary>
+        private void DeserializeDespawnedInScenePlacedNetworkObjects()
+        {
+            // Process all de-spawned in-scene NetworkObjects for this network session
+            m_DespawnedInSceneObjects.Clear();
+            InternalBuffer.ReadValueSafe(out int despawnedObjectsCount);
+            var sceneCache = new Dictionary<int, Dictionary<uint, NetworkObject>>();
+
+            for (int i = 0; i < despawnedObjectsCount; i++)
+            {
+                // We just need to get the scene
+                ByteUnpacker.ReadValuePacked(InternalBuffer, out int networkSceneHandle);
+                ByteUnpacker.ReadValuePacked(InternalBuffer, out uint globalObjectIdHash);
+                var sceneRelativeNetworkObjects = new Dictionary<uint, NetworkObject>();
+                if (!sceneCache.ContainsKey(networkSceneHandle))
+                {
+                    if (m_NetworkManager.SceneManager.ServerSceneHandleToClientSceneHandle.ContainsKey(networkSceneHandle))
+                    {
+                        var localSceneHandle = m_NetworkManager.SceneManager.ServerSceneHandleToClientSceneHandle[networkSceneHandle];
+                        if (m_NetworkManager.SceneManager.ScenesLoaded.ContainsKey(localSceneHandle))
+                        {
+                            var objectRelativeScene = m_NetworkManager.SceneManager.ScenesLoaded[localSceneHandle];
+
+                            // Find all active and non-active in-scene placed NetworkObjects
+                            var inSceneNetworkObjects = UnityEngine.Object.FindObjectsOfType<NetworkObject>(includeInactive: true).Where((c) =>
+                            c.GetSceneOriginHandle() == localSceneHandle && (c.IsSceneObject != false)).ToList();
+
+                            foreach (var inSceneObject in inSceneNetworkObjects)
+                            {
+                                if (!sceneRelativeNetworkObjects.ContainsKey(inSceneObject.GlobalObjectIdHash))
+                                {
+                                    sceneRelativeNetworkObjects.Add(inSceneObject.GlobalObjectIdHash, inSceneObject);
+                                }
+                            }
+                            // Add this to a cache so we don't have to run this potentially multiple times (nothing will spawn or despawn during this time
+                            sceneCache.Add(networkSceneHandle, sceneRelativeNetworkObjects);
+                        }
+                        else
+                        {
+                            UnityEngine.Debug.LogError($"In-Scene NetworkObject GlobalObjectIdHash ({globalObjectIdHash}) cannot find its relative local scene handle {localSceneHandle}!");
+                        }
+                    }
+                    else
+                    {
+                        UnityEngine.Debug.LogError($"In-Scene NetworkObject GlobalObjectIdHash ({globalObjectIdHash}) cannot find its relative NetworkSceneHandle {networkSceneHandle}!");
+                    }
+                }
+                else // Use the cached NetworkObjects if they exist
+                {
+                    sceneRelativeNetworkObjects = sceneCache[networkSceneHandle];
+                }
+
+                // Now find the in-scene NetworkObject with the current GlobalObjectIdHash we are looking for
+                if (sceneRelativeNetworkObjects.ContainsKey(globalObjectIdHash))
+                {
+                    // Since this is a NetworkObject that was never spawned, we just need to send a notification
+                    // out that it was despawned so users can make adjustments
+                    sceneRelativeNetworkObjects[globalObjectIdHash].InvokeBehaviourNetworkDespawn();
+                    if (!m_NetworkManager.SceneManager.ScenePlacedObjects.ContainsKey(globalObjectIdHash))
+                    {
+                        m_NetworkManager.SceneManager.ScenePlacedObjects.Add(globalObjectIdHash, new Dictionary<int, NetworkObject>());
+                    }
+
+                    if (!m_NetworkManager.SceneManager.ScenePlacedObjects[globalObjectIdHash].ContainsKey(sceneRelativeNetworkObjects[globalObjectIdHash].GetSceneOriginHandle()))
+                    {
+                        m_NetworkManager.SceneManager.ScenePlacedObjects[globalObjectIdHash].Add(sceneRelativeNetworkObjects[globalObjectIdHash].GetSceneOriginHandle(), sceneRelativeNetworkObjects[globalObjectIdHash]);
+                    }
+                }
+                else
+                {
+                    UnityEngine.Debug.LogError($"In-Scene NetworkObject GlobalObjectIdHash ({globalObjectIdHash}) could not be found!");
+                }
+            }
+        }
+
         /// <summary>
         /// Client Side:
         /// During the processing of a server sent Event_Sync, this method will be called for each scene once
@@ -734,72 +868,9 @@ namespace Unity.Netcode
                     }
                 }
 
-                // Process all de-spawned in-scene NetworkObjects for this network session
-                m_DespawnedInSceneObjects.Clear();
-                InternalBuffer.ReadValueSafe(out int despawnedObjectsCount);
-                var sceneCache = new Dictionary<int, Dictionary<uint, NetworkObject>>();
+                // Now deserialize the despawned in-scene placed NetworkObjects list (if any)
+                DeserializeDespawnedInScenePlacedNetworkObjects();
 
-                for (int i = 0; i < despawnedObjectsCount; i++)
-                {
-                    // We just need to get the scene
-                    ByteUnpacker.ReadValuePacked(InternalBuffer, out int networkSceneHandle);
-                    ByteUnpacker.ReadValuePacked(InternalBuffer, out uint globalObjectIdHash);
-                    var sceneRelativeNetworkObjects = new Dictionary<uint, NetworkObject>();
-                    if (!sceneCache.ContainsKey(networkSceneHandle))
-                    {
-                        if (m_NetworkManager.SceneManager.ServerSceneHandleToClientSceneHandle.ContainsKey(networkSceneHandle))
-                        {
-                            var localSceneHandle = m_NetworkManager.SceneManager.ServerSceneHandleToClientSceneHandle[networkSceneHandle];
-                            if (m_NetworkManager.SceneManager.ScenesLoaded.ContainsKey(localSceneHandle))
-                            {
-                                var objectRelativeScene = m_NetworkManager.SceneManager.ScenesLoaded[localSceneHandle];
-                                var inSceneNetworkObjects = UnityEngine.Object.FindObjectsOfType<NetworkObject>().Where((c) =>
-                                c.GetSceneOriginHandle() == localSceneHandle && (c.IsSceneObject != false)).ToList();
-
-                                foreach (var inSceneObject in inSceneNetworkObjects)
-                                {
-                                    sceneRelativeNetworkObjects.Add(inSceneObject.GlobalObjectIdHash, inSceneObject);
-                                }
-                                // Add this to a cache so we don't have to run this potentially multiple times (nothing will spawn or despawn during this time
-                                sceneCache.Add(networkSceneHandle, sceneRelativeNetworkObjects);
-                            }
-                            else
-                            {
-                                UnityEngine.Debug.LogError($"In-Scene NetworkObject GlobalObjectIdHash ({globalObjectIdHash}) cannot find its relative local scene handle {localSceneHandle}!");
-                            }
-                        }
-                        else
-                        {
-                            UnityEngine.Debug.LogError($"In-Scene NetworkObject GlobalObjectIdHash ({globalObjectIdHash}) cannot find its relative NetworkSceneHandle {networkSceneHandle}!");
-                        }
-                    }
-                    else // Use the cached NetworkObjects if they exist
-                    {
-                        sceneRelativeNetworkObjects = sceneCache[networkSceneHandle];
-                    }
-
-                    // Now find the in-scene NetworkObject with the current GlobalObjectIdHash we are looking for
-                    if (sceneRelativeNetworkObjects.ContainsKey(globalObjectIdHash))
-                    {
-                        // Since this is a NetworkObject that was never spawned, we just need to send a notification
-                        // out that it was despawned so users can make adjustments
-                        sceneRelativeNetworkObjects[globalObjectIdHash].InvokeBehaviourNetworkDespawn();
-                        if (!m_NetworkManager.SceneManager.ScenePlacedObjects.ContainsKey(globalObjectIdHash))
-                        {
-                            m_NetworkManager.SceneManager.ScenePlacedObjects.Add(globalObjectIdHash, new Dictionary<int, NetworkObject>());
-                        }
-
-                        if (!m_NetworkManager.SceneManager.ScenePlacedObjects[globalObjectIdHash].ContainsKey(sceneRelativeNetworkObjects[globalObjectIdHash].GetSceneOriginHandle()))
-                        {
-                            m_NetworkManager.SceneManager.ScenePlacedObjects[globalObjectIdHash].Add(sceneRelativeNetworkObjects[globalObjectIdHash].GetSceneOriginHandle(), sceneRelativeNetworkObjects[globalObjectIdHash]);
-                        }
-
-                    }
-                    else
-                    {
-                        UnityEngine.Debug.LogError($"In-Scene NetworkObject GlobalObjectIdHash ({globalObjectIdHash}) could not be found!");
-                    }
-                }
             }
             finally
             {

Runtime/SceneManagement/SceneEventProgress.cs

@@ -58,12 +58,13 @@ namespace Unity.Netcode
         /// <summary>
         /// List of clientIds of those clients that is done loading the scene.
         /// </summary>
-        internal List<ulong> DoneClients { get; } = new List<ulong>();
+        internal Dictionary<ulong, bool> ClientsProcessingSceneEvent { get; } = new Dictionary<ulong, bool>();
+        internal List<ulong> ClientsThatDisconnected = new List<ulong>();
 
         /// <summary>
-        /// The local time when the scene event was "roughly started"
+        /// This is when the current scene event will have timed out
         /// </summary>
-        internal float TimeAtInitiation { get; }
+        internal float WhenSceneEventHasTimedOut;
 
         /// <summary>
         /// Delegate type for when the switch scene progress is completed. Either by all clients done loading the scene or by time out.
@@ -75,17 +76,15 @@ namespace Unity.Netcode
         /// </summary>
         internal OnCompletedDelegate OnComplete;
 
-        /// <summary>
-        /// Is this scene switch progresses completed, all clients are done loading the scene or a timeout has occurred.
-        /// </summary>
-        internal bool IsCompleted { get; private set; }
-
-        internal bool TimedOut { get; private set; }
+        internal Action<uint> OnSceneEventCompleted;
 
         /// <summary>
-        /// If all clients are done loading the scene, at the moment of completed.
+        /// This will make sure that we only have timed out if we never completed
         /// </summary>
-        internal bool AreAllClientsDoneLoading { get; private set; }
+        internal bool HasTimedOut()
+        {
+            return WhenSceneEventHasTimedOut <= Time.realtimeSinceStartup;
+        }
 
         /// <summary>
         /// The hash value generated from the full scene path
@@ -93,9 +92,10 @@ namespace Unity.Netcode
         internal uint SceneHash { get; set; }
 
         internal Guid Guid { get; } = Guid.NewGuid();
+        internal uint SceneEventId;
 
         private Coroutine m_TimeOutCoroutine;
-        private AsyncOperation m_SceneLoadOperation;
+        private AsyncOperation m_AsyncOperation;
 
         private NetworkManager m_NetworkManager { get; }
 
@@ -105,21 +105,62 @@ namespace Unity.Netcode
 
         internal LoadSceneMode LoadSceneMode;
 
-        internal List<ulong> ClientsThatStartedSceneEvent;
+        internal List<ulong> GetClientsWithStatus(bool completedSceneEvent)
+        {
+            var clients = new List<ulong>();
+            foreach (var clientStatus in ClientsProcessingSceneEvent)
+            {
+                if (clientStatus.Value == completedSceneEvent)
+                {
+                    clients.Add(clientStatus.Key);
+                }
+            }
+
+            // If we are getting the list of clients that have not completed the
+            // scene event, then add any clients that disconnected during this
+            // scene event.
+            if (!completedSceneEvent)
+            {
+                clients.AddRange(ClientsThatDisconnected);
+            }
+            return clients;
+        }
 
         internal SceneEventProgress(NetworkManager networkManager, SceneEventProgressStatus status = SceneEventProgressStatus.Started)
         {
             if (status == SceneEventProgressStatus.Started)
             {
-                // Track the clients that were connected when we started this event
-                ClientsThatStartedSceneEvent = new List<ulong>(networkManager.ConnectedClientsIds);
                 m_NetworkManager = networkManager;
-                m_TimeOutCoroutine = m_NetworkManager.StartCoroutine(TimeOutSceneEventProgress());
-                TimeAtInitiation = Time.realtimeSinceStartup;
+
+                if (networkManager.IsServer)
+                {
+                    m_NetworkManager.OnClientDisconnectCallback += OnClientDisconnectCallback;
+                    // Track the clients that were connected when we started this event
+                    foreach (var connectedClientId in networkManager.ConnectedClientsIds)
+                    {
+                        ClientsProcessingSceneEvent.Add(connectedClientId, false);
+                    }
+
+                    WhenSceneEventHasTimedOut = Time.realtimeSinceStartup + networkManager.NetworkConfig.LoadSceneTimeOut;
+                    m_TimeOutCoroutine = m_NetworkManager.StartCoroutine(TimeOutSceneEventProgress());
+                }
             }
             Status = status;
         }
 
+        /// <summary>
+        /// Remove the client from the clients processing the current scene event
+        /// Add this client to the clients that disconnected list
+        /// </summary>
+        private void OnClientDisconnectCallback(ulong clientId)
+        {
+            if (ClientsProcessingSceneEvent.ContainsKey(clientId))
+            {
+                ClientsThatDisconnected.Add(clientId);
+                ClientsProcessingSceneEvent.Remove(clientId);
+            }
+        }
+
         /// <summary>
         /// Coroutine that checks to see if the scene event is complete every network tick period.
         /// This will handle completing the scene event when one or more client(s) disconnect(s)
@@ -129,79 +170,104 @@ namespace Unity.Netcode
         internal IEnumerator TimeOutSceneEventProgress()
         {
             var waitForNetworkTick = new WaitForSeconds(1.0f / m_NetworkManager.NetworkConfig.TickRate);
-            while (!TimedOut && !IsCompleted)
+            while (!HasTimedOut())
             {
                 yield return waitForNetworkTick;
 
-                CheckCompletion();
-                if (!IsCompleted)
-                {
-                    TimedOut = TimeAtInitiation - Time.realtimeSinceStartup >= m_NetworkManager.NetworkConfig.LoadSceneTimeOut;
-                }
+                TryFinishingSceneEventProgress();
             }
         }
 
-        internal void AddClientAsDone(ulong clientId)
-        {
-            DoneClients.Add(clientId);
-            CheckCompletion();
-        }
-
-        internal void RemoveClientAsDone(ulong clientId)
-        {
-            DoneClients.Remove(clientId);
-            CheckCompletion();
-        }
-
-        internal void SetSceneLoadOperation(AsyncOperation sceneLoadOperation)
-        {
-            m_SceneLoadOperation = sceneLoadOperation;
-            m_SceneLoadOperation.completed += operation => CheckCompletion();
-        }
-
         /// <summary>
-        /// Called only on the server-side during integration test (NetcodeIntegrationTest specific)
-        /// scene loading and unloading.
-        ///
-        /// Note: During integration testing we must queue all scene loading and unloading requests for
-        /// both the server and all clients so they can be processed in a FIFO/linear fashion to avoid
-        /// conflicts when the  <see cref="SceneManager.sceneLoaded"/> and <see cref="SceneManager.sceneUnloaded"/>
-        /// events are triggered. The Completed action simulates the <see cref="AsyncOperation.completed"/> event.
-        /// (See: Unity.Netcode.TestHelpers.Runtime.IntegrationTestSceneHandler)
+        /// Sets the client's scene event progress to finished/true
         /// </summary>
-        internal void SetSceneLoadOperation(ISceneManagerHandler.SceneEventAction sceneEventAction)
+        internal void ClientFinishedSceneEvent(ulong clientId)
         {
-            sceneEventAction.Completed = SetComplete;
+            if (ClientsProcessingSceneEvent.ContainsKey(clientId))
+            {
+                ClientsProcessingSceneEvent[clientId] = true;
+                TryFinishingSceneEventProgress();
+            }
         }
 
         /// <summary>
-        /// Finalizes the SceneEventProgress
+        /// Determines if the scene event has finished for both
+        /// client(s) and server.
         /// </summary>
-        internal void SetComplete()
+        /// <remarks>
+        /// The server checks if all known clients processing this scene event
+        /// have finished and then it returns its local AsyncOperation status.
+        /// Clients finish when their AsyncOperation finishes.
+        /// </remarks>
+        private bool HasFinished()
         {
-            IsCompleted = true;
-            AreAllClientsDoneLoading = true;
-
-            // If OnComplete is not registered or it is and returns true then remove this from the progress tracking
-            if (OnComplete == null || (OnComplete != null && OnComplete.Invoke(this)))
+            // If the network session is terminated/terminating then finish tracking
+            // this scene event
+            if (!IsNetworkSessionActive())
             {
-                m_NetworkManager.SceneManager.SceneEventProgressTracking.Remove(Guid);
+                return true;
             }
-            m_NetworkManager.StopCoroutine(m_TimeOutCoroutine);
-        }
 
-        internal void CheckCompletion()
-        {
-            try
+            // Clients skip over this
+            foreach (var clientStatus in ClientsProcessingSceneEvent)
             {
-                if ((!IsCompleted && DoneClients.Count == m_NetworkManager.ConnectedClientsList.Count && (m_SceneLoadOperation == null || m_SceneLoadOperation.isDone)) || (!IsCompleted && TimedOut))
+                if (!clientStatus.Value)
                 {
-                    SetComplete();
+                    return false;
                 }
             }
-            catch (Exception ex)
+
+            // Return the local scene event's AsyncOperation status
+            return m_AsyncOperation.isDone;
+        }
+
+        /// <summary>
+        /// Sets the AsyncOperation for the scene load/unload event
+        /// </summary>
+        internal void SetAsyncOperation(AsyncOperation asyncOperation)
+        {
+            m_AsyncOperation = asyncOperation;
+            m_AsyncOperation.completed += new Action<AsyncOperation>(asyncOp2 =>
             {
-                Debug.LogException(ex);
+                // Don't invoke the callback if the network session is disconnected
+                // during a SceneEventProgress
+                if (IsNetworkSessionActive())
+                {
+                    OnSceneEventCompleted?.Invoke(SceneEventId);
+                }
+
+                // Go ahead and try finishing even if the network session is terminated/terminating
+                // as we might need to stop the coroutine
+                TryFinishingSceneEventProgress();
+            });
+        }
+
+
+        internal bool IsNetworkSessionActive()
+        {
+            return m_NetworkManager != null && m_NetworkManager.IsListening && !m_NetworkManager.ShutdownInProgress;
+        }
+
+        /// <summary>
+        /// Will try to finish the current scene event in progress as long as
+        /// all conditions are met.
+        /// </summary>
+        internal void TryFinishingSceneEventProgress()
+        {
+            if (HasFinished() || HasTimedOut())
+            {
+                // Don't attempt to finalize this scene event if we are no longer listening or a shutdown is in progress
+                if (IsNetworkSessionActive())
+                {
+                    OnComplete?.Invoke(this);
+                    m_NetworkManager.SceneManager.SceneEventProgressTracking.Remove(Guid);
+                    m_NetworkManager.OnClientDisconnectCallback -= OnClientDisconnectCallback;
+                }
+
+                if (m_TimeOutCoroutine != null)
+                {
+                    m_NetworkManager.StopCoroutine(m_TimeOutCoroutine);
+                }
             }
         }
     }

Runtime/Serialization/BitReader.cs

@@ -21,6 +21,8 @@ namespace Unity.Netcode
 
         private const int k_BitsPerByte = 8;
 
+        private int BytePosition => m_BitPosition >> 3;
+
         /// <summary>
         /// Whether or not the current BitPosition is evenly divisible by 8. I.e. whether or not the BitPosition is at a byte boundary.
         /// </summary>
@@ -98,11 +100,6 @@ namespace Unity.Netcode
                 throw new ArgumentOutOfRangeException(nameof(bitCount), "Cannot read more than 64 bits from a 64-bit value!");
             }
 
-            if (bitCount < 0)
-            {
-                throw new ArgumentOutOfRangeException(nameof(bitCount), "Cannot read fewer than 0 bits!");
-            }
-
             int checkPos = (int)(m_BitPosition + bitCount);
             if (checkPos > m_AllowedBitwiseReadMark)
             {
@@ -165,7 +162,7 @@ namespace Unity.Netcode
 #endif
 
             int offset = m_BitPosition & 7;
-            int pos = m_BitPosition >> 3;
+            int pos = BytePosition;
             bit = (m_BufferPointer[pos] & (1 << offset)) != 0;
             ++m_BitPosition;
         }
@@ -175,7 +172,7 @@ namespace Unity.Netcode
         {
             var val = new T();
             byte* ptr = ((byte*)&val) + offsetBytes;
-            byte* bufferPointer = m_BufferPointer + m_Position;
+            byte* bufferPointer = m_BufferPointer + BytePosition;
             UnsafeUtility.MemCpy(ptr, bufferPointer, bytesToRead);
 
             m_BitPosition += bytesToRead * k_BitsPerByte;

Runtime/Serialization/BitWriter.cs

@@ -29,6 +29,8 @@ namespace Unity.Netcode
             get => (m_BitPosition & 7) == 0;
         }
 
+        private int BytePosition => m_BitPosition >> 3;
+
         internal unsafe BitWriter(FastBufferWriter writer)
         {
             m_Writer = writer;
@@ -181,7 +183,7 @@ namespace Unity.Netcode
 #endif
 
             int offset = m_BitPosition & 7;
-            int pos = m_BitPosition >> 3;
+            int pos = BytePosition;
             ++m_BitPosition;
             m_BufferPointer[pos] = (byte)(bit ? (m_BufferPointer[pos] & ~(1 << offset)) | (1 << offset) : (m_BufferPointer[pos] & ~(1 << offset)));
         }
@@ -190,7 +192,7 @@ namespace Unity.Netcode
         private unsafe void WritePartialValue<T>(T value, int bytesToWrite, int offsetBytes = 0) where T : unmanaged
         {
             byte* ptr = ((byte*)&value) + offsetBytes;
-            byte* bufferPointer = m_BufferPointer + m_Position;
+            byte* bufferPointer = m_BufferPointer + BytePosition;
             UnsafeUtility.MemCpy(bufferPointer, ptr, bytesToWrite);
 
             m_BitPosition += bytesToWrite * k_BitsPerByte;

Runtime/Serialization/BufferSerializerReader.cs

@@ -34,7 +34,7 @@ namespace Unity.Netcode
         public void SerializeValue<T>(ref T[] value, FastBufferWriter.ForEnums unused = default) where T : unmanaged, Enum => m_Reader.ReadValueSafe(out value);
         public void SerializeValue<T>(ref T value, FastBufferWriter.ForStructs unused = default) where T : unmanaged, INetworkSerializeByMemcpy => m_Reader.ReadValueSafe(out value);
         public void SerializeValue<T>(ref T[] value, FastBufferWriter.ForStructs unused = default) where T : unmanaged, INetworkSerializeByMemcpy => m_Reader.ReadValueSafe(out value);
-        public void SerializeValue<T>(ref T value, FastBufferWriter.ForNetworkSerializable unused = default) where T : INetworkSerializable, new() => m_Reader.ReadValue(out value);
+        public void SerializeValue<T>(ref T value, FastBufferWriter.ForNetworkSerializable unused = default) where T : INetworkSerializable, new() => m_Reader.ReadNetworkSerializableInPlace(ref value);
         public void SerializeValue<T>(ref T[] value, FastBufferWriter.ForNetworkSerializable unused = default) where T : INetworkSerializable, new() => m_Reader.ReadValue(out value);
 
         public void SerializeValue<T>(ref T value, FastBufferWriter.ForFixedStrings unused = default)

Runtime/Serialization/FastBufferReader.cs

@@ -461,6 +461,19 @@ namespace Unity.Netcode
             }
         }
 
+        /// <summary>
+        /// Read an INetworkSerializable in-place, without constructing a new one
+        /// Note that this will NOT check for null before calling NetworkSerialize
+        /// </summary>
+        /// <typeparam name="T"></typeparam>
+        /// <param name="value">INetworkSerializable instance</param>
+        /// <exception cref="NotImplementedException"></exception>
+        public void ReadNetworkSerializableInPlace<T>(ref T value) where T : INetworkSerializable
+        {
+            var bufferSerializer = new BufferSerializer<BufferSerializerReader>(new BufferSerializerReader(this));
+            value.NetworkSerialize(bufferSerializer);
+        }
+
         /// <summary>
         /// Reads a string
         /// NOTE: ALLOCATES
@@ -1310,5 +1323,24 @@ namespace Unity.Netcode
             value.Length = length;
             ReadBytesSafe(value.GetUnsafePtr(), length);
         }
+
+
+        /// <summary>
+        /// Read a FixedString value.
+        ///
+        /// "Safe" version - automatically performs bounds checking. Less efficient than bounds checking
+        /// for multiple reads at once by calling TryBeginRead.
+        /// </summary>
+        /// <param name="value">the value to read</param>
+        /// <param name="unused">An unused parameter used for enabling overload resolution based on generic constraints</param>
+        /// <typeparam name="T">The type being serialized</typeparam>
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public unsafe void ReadValueSafeInPlace<T>(ref T value, FastBufferWriter.ForFixedStrings unused = default)
+            where T : unmanaged, INativeList<byte>, IUTF8Bytes
+        {
+            ReadUnmanagedSafe(out int length);
+            value.Length = length;
+            ReadBytesSafe(value.GetUnsafePtr(), length);
+        }
     }
 }

Runtime/Serialization/NetworkObjectReference.cs

@@ -139,7 +139,16 @@ namespace Unity.Netcode
         /// </summary>
         /// <param name="networkObjectRef">The <see cref="NetworkObjectReference"/> to convert from.</param>
         /// <returns>This returns the <see cref="GameObject"/> that the <see cref="NetworkObject"/> is attached to and is referenced by the <see cref="NetworkObjectReference"/> passed in as a parameter</returns>
-        public static implicit operator GameObject(NetworkObjectReference networkObjectRef) => Resolve(networkObjectRef).gameObject;
+        public static implicit operator GameObject(NetworkObjectReference networkObjectRef)
+        {
+            var networkObject = Resolve(networkObjectRef);
+            if (networkObject != null)
+            {
+                return networkObject.gameObject;
+            }
+
+            return null;
+        }
 
         /// <summary>
         /// Implicitly convert <see cref="GameObject"/> to <see cref="NetworkObject"/>.

Runtime/Spawning/NetworkPrefabHandler.cs

@@ -119,8 +119,7 @@ namespace Unity.Netcode
                         // Now we register all
                         foreach (var gameObject in networkPrefabOverrides)
                         {
-                            var targetNetworkObject = gameObject.GetComponent<NetworkObject>();
-                            if (targetNetworkObject != null)
+                            if (gameObject.TryGetComponent<NetworkObject>(out var targetNetworkObject))
                             {
                                 if (!m_PrefabInstanceToPrefabAsset.ContainsKey(targetNetworkObject.GlobalObjectIdHash))
                                 {

Runtime/Spawning/NetworkSpawnManager.cs

@@ -213,11 +213,11 @@ namespace Unity.Netcode
                 return;
             }
 
+            networkObject.OwnerClientId = NetworkManager.ServerClientId;
+
             // Server removes the entry and takes over ownership before notifying
             UpdateOwnershipTable(networkObject, NetworkManager.ServerClientId, true);
 
-            networkObject.OwnerClientId = NetworkManager.ServerClientId;
-
             var message = new ChangeOwnershipMessage
             {
                 NetworkObjectId = networkObject.NetworkObjectId,
@@ -278,11 +278,14 @@ namespace Unity.Netcode
                 NetworkObjectId = networkObject.NetworkObjectId,
                 OwnerClientId = networkObject.OwnerClientId
             };
-            var size = NetworkManager.SendMessage(ref message, NetworkDelivery.ReliableSequenced, NetworkManager.ConnectedClientsIds);
 
             foreach (var client in NetworkManager.ConnectedClients)
             {
-                NetworkManager.NetworkMetrics.TrackOwnershipChangeSent(client.Key, networkObject, size);
+                if (networkObject.IsNetworkVisibleTo(client.Value.ClientId))
+                {
+                    var size = NetworkManager.SendMessage(ref message, NetworkDelivery.ReliableSequenced, client.Value.ClientId);
+                    NetworkManager.NetworkMetrics.TrackOwnershipChangeSent(client.Key, networkObject, size);
+                }
             }
         }
 
@@ -314,48 +317,33 @@ namespace Unity.Netcode
         }
 
         /// <summary>
-        /// Should only run on the client
+        /// Creates a local NetowrkObject to be spawned.
         /// </summary>
-        internal NetworkObject CreateLocalNetworkObject(bool isSceneObject, uint globalObjectIdHash, ulong ownerClientId, ulong? parentNetworkId, int? networkSceneHandle, Vector3? position, Quaternion? rotation, bool isReparented = false)
+        /// <remarks>
+        /// For most cases this is client-side only, with the exception of when the server
+        /// is spawning a player.
+        /// </remarks>
+        internal NetworkObject CreateLocalNetworkObject(NetworkObject.SceneObject sceneObject)
         {
-            NetworkObject parentNetworkObject = null;
+            NetworkObject networkObject = null;
+            var globalObjectIdHash = sceneObject.Header.Hash;
+            var position = sceneObject.Header.HasTransform ? sceneObject.Transform.Position : default;
+            var rotation = sceneObject.Header.HasTransform ? sceneObject.Transform.Rotation : default;
+            var scale = sceneObject.Header.HasTransform ? sceneObject.Transform.Scale : default;
+            var parentNetworkId = sceneObject.Header.HasParent ? sceneObject.ParentObjectId : default;
+            var worldPositionStays = sceneObject.Header.HasParent ? sceneObject.WorldPositionStays : true;
+            var isSpawnedByPrefabHandler = false;
 
-            if (parentNetworkId != null && !isReparented)
-            {
-                if (SpawnedObjects.TryGetValue(parentNetworkId.Value, out NetworkObject networkObject))
-                {
-                    parentNetworkObject = networkObject;
-                }
-                else
-                {
-                    if (NetworkLog.CurrentLogLevel <= LogLevel.Normal)
-                    {
-                        NetworkLog.LogWarning("Cannot find parent. Parent objects always have to be spawned and replicated BEFORE the child");
-                    }
-                }
-            }
-
-            if (!NetworkManager.NetworkConfig.EnableSceneManagement || !isSceneObject)
+            // If scene management is disabled or the NetworkObject was dynamically spawned
+            if (!NetworkManager.NetworkConfig.EnableSceneManagement || !sceneObject.Header.IsSceneObject)
             {
                 // If the prefab hash has a registered INetworkPrefabInstanceHandler derived class
                 if (NetworkManager.PrefabHandler.ContainsHandler(globalObjectIdHash))
                 {
                     // Let the handler spawn the NetworkObject
-                    var networkObject = NetworkManager.PrefabHandler.HandleNetworkPrefabSpawn(globalObjectIdHash, ownerClientId, position.GetValueOrDefault(Vector3.zero), rotation.GetValueOrDefault(Quaternion.identity));
-
+                    networkObject = NetworkManager.PrefabHandler.HandleNetworkPrefabSpawn(globalObjectIdHash, sceneObject.Header.OwnerClientId, position, rotation);
                     networkObject.NetworkManagerOwner = NetworkManager;
-
-                    if (parentNetworkObject != null)
-                    {
-                        networkObject.transform.SetParent(parentNetworkObject.transform, true);
-                    }
-
-                    if (NetworkSceneManager.IsSpawnedObjectsPendingInDontDestroyOnLoad)
-                    {
-                        UnityEngine.Object.DontDestroyOnLoad(networkObject.gameObject);
-                    }
-
-                    return networkObject;
+                    isSpawnedByPrefabHandler = true;
                 }
                 else
                 {
@@ -383,31 +371,18 @@ namespace Unity.Netcode
                         {
                             NetworkLog.LogError($"Failed to create object locally. [{nameof(globalObjectIdHash)}={globalObjectIdHash}]. {nameof(NetworkPrefab)} could not be found. Is the prefab registered with {nameof(NetworkManager)}?");
                         }
-
-                        return null;
                     }
-
-                    // Otherwise, instantiate an instance of the NetworkPrefab linked to the prefabHash
-                    var networkObject = ((position == null && rotation == null) ? UnityEngine.Object.Instantiate(networkPrefabReference) : UnityEngine.Object.Instantiate(networkPrefabReference, position.GetValueOrDefault(Vector3.zero), rotation.GetValueOrDefault(Quaternion.identity))).GetComponent<NetworkObject>();
-
-                    networkObject.NetworkManagerOwner = NetworkManager;
-
-                    if (parentNetworkObject != null)
+                    else
                     {
-                        networkObject.transform.SetParent(parentNetworkObject.transform, true);
+                        // Create prefab instance
+                        networkObject = UnityEngine.Object.Instantiate(networkPrefabReference).GetComponent<NetworkObject>();
+                        networkObject.NetworkManagerOwner = NetworkManager;
                     }
-
-                    if (NetworkSceneManager.IsSpawnedObjectsPendingInDontDestroyOnLoad)
-                    {
-                        UnityEngine.Object.DontDestroyOnLoad(networkObject.gameObject);
-                    }
-
-                    return networkObject;
                 }
             }
-            else
+            else // Get the in-scene placed NetworkObject
             {
-                var networkObject = NetworkManager.SceneManager.GetSceneRelativeInSceneNetworkObject(globalObjectIdHash, networkSceneHandle);
+                networkObject = NetworkManager.SceneManager.GetSceneRelativeInSceneNetworkObject(globalObjectIdHash, sceneObject.NetworkSceneHandle);
 
                 if (networkObject == null)
                 {
@@ -415,17 +390,78 @@ namespace Unity.Netcode
                     {
                         NetworkLog.LogError($"{nameof(NetworkPrefab)} hash was not found! In-Scene placed {nameof(NetworkObject)} soft synchronization failure for Hash: {globalObjectIdHash}!");
                     }
-
-                    return null;
                 }
 
-                if (parentNetworkObject != null)
+                // Since this NetworkObject is an in-scene placed NetworkObject, if it is disabled then enable it so
+                // NetworkBehaviours will have their OnNetworkSpawn method invoked
+                if (networkObject != null && !networkObject.gameObject.activeInHierarchy)
                 {
-                    networkObject.transform.SetParent(parentNetworkObject.transform, true);
+                    networkObject.gameObject.SetActive(true);
+                }
+            }
+
+            if (networkObject != null)
+            {
+                // SPECIAL CASE:
+                // This is a special case scenario where a late joining client has joined and loaded one or
+                // more scenes that contain nested in-scene placed NetworkObject children yet the server's
+                // synchronization information does not indicate the NetworkObject in question has a parent.
+                // Under this scenario, we want to remove the parent before spawning and setting the transform values.
+                if (sceneObject.Header.IsSceneObject && !sceneObject.Header.HasParent && networkObject.transform.parent != null)
+                {
+                    // if the in-scene placed NetworkObject has a parent NetworkObject but the synchronization information does not
+                    // include parenting, then we need to force the removal of that parent
+                    if (networkObject.transform.parent.GetComponent<NetworkObject>() != null)
+                    {
+                        // remove the parent
+                        networkObject.ApplyNetworkParenting(true, true);
+                    }
                 }
 
-                return networkObject;
+                // Set the transform unless we were spawned by a prefab handler
+                // Note: prefab handlers are provided the position and rotation
+                // but it is up to the user to set those values
+                if (sceneObject.Header.HasTransform && !isSpawnedByPrefabHandler)
+                {
+                    if (worldPositionStays)
+                    {
+                        networkObject.transform.position = position;
+                        networkObject.transform.rotation = rotation;
+                    }
+                    else
+                    {
+                        networkObject.transform.localPosition = position;
+                        networkObject.transform.localRotation = rotation;
+                    }
+
+                    // SPECIAL CASE:
+                    // Since players are created uniquely we don't apply scale because
+                    // the ConnectionApprovalResponse does not currently provide the
+                    // ability to specify scale. So, we just use the default scale of
+                    // the network prefab used to represent the player.
+                    // Note: not doing this would set the player's scale to zero since
+                    // that is the default value of Vector3.
+                    if (!sceneObject.Header.IsPlayerObject)
+                    {
+                        networkObject.transform.localScale = scale;
+                    }
+                }
+
+                if (sceneObject.Header.HasParent)
+                {
+                    // Go ahead and set network parenting properties
+                    networkObject.SetNetworkParenting(parentNetworkId, worldPositionStays);
+                }
+
+
+                // Dynamically spawned NetworkObjects that occur during a LoadSceneMode.Single load scene event are migrated into the DDOL
+                // until the scene is loaded. They are then migrated back into the newly loaded and currently active scene.
+                if (!sceneObject.Header.IsSceneObject && NetworkSceneManager.IsSpawnedObjectsPendingInDontDestroyOnLoad)
+                {
+                    UnityEngine.Object.DontDestroyOnLoad(networkObject.gameObject);
+                }
             }
+            return networkObject;
         }
 
         // Ran on both server and client
@@ -545,7 +581,6 @@ namespace Unity.Netcode
                 }
             }
 
-            networkObject.SetCachedParent(networkObject.transform.parent);
             networkObject.ApplyNetworkParenting();
             NetworkObject.CheckOrphanChildren();
 
@@ -575,8 +610,6 @@ namespace Unity.Netcode
             };
             var size = NetworkManager.SendMessage(ref message, NetworkDelivery.ReliableFragmentedSequenced, clientId);
             NetworkManager.NetworkMetrics.TrackObjectSpawnSent(clientId, networkObject, size);
-
-            networkObject.MarkVariablesDirty();
         }
 
         internal ulong? GetSpawnParentId(NetworkObject networkObject)
@@ -745,15 +778,26 @@ namespace Unity.Netcode
             }
 
             // If we are shutting down the NetworkManager, then ignore resetting the parent
-            if (!NetworkManager.ShutdownInProgress)
+            // and only attempt to remove the child's parent on the server-side
+            if (!NetworkManager.ShutdownInProgress && NetworkManager.IsServer)
             {
                 // Move child NetworkObjects to the root when parent NetworkObject is destroyed
                 foreach (var spawnedNetObj in SpawnedObjectsList)
                 {
-                    var (isReparented, latestParent) = spawnedNetObj.GetNetworkParenting();
-                    if (isReparented && latestParent == networkObject.NetworkObjectId)
+                    var latestParent = spawnedNetObj.GetNetworkParenting();
+                    if (latestParent.HasValue && latestParent.Value == networkObject.NetworkObjectId)
                     {
-                        spawnedNetObj.gameObject.transform.parent = null;
+                        // Try to remove the parent using the cached WorldPositioNStays value
+                        // Note: WorldPositionStays will still default to true if this was an
+                        // in-scene placed NetworkObject and parenting was predefined in the
+                        // scene via the editor.
+                        if (!spawnedNetObj.TryRemoveParentCachedWorldPositionStays())
+                        {
+                            if (NetworkLog.CurrentLogLevel <= LogLevel.Normal)
+                            {
+                                NetworkLog.LogError($"{nameof(NetworkObject)} #{spawnedNetObj.NetworkObjectId} could not be moved to the root when its parent {nameof(NetworkObject)} #{networkObject.NetworkObjectId} was being destroyed");
+                            }
+                        }
 
                         if (NetworkLog.CurrentLogLevel <= LogLevel.Normal)
                         {

Runtime/Timing/NetworkTime.cs

@@ -25,7 +25,7 @@ namespace Unity.Netcode
         public double TickOffset => m_CachedTickOffset;
 
         /// <summary>
-        /// Gets the current time. This is a non fixed time value and similar to <see cref="Time.time"/>
+        /// Gets the current time. This is a non fixed time value and similar to <see cref="Time.time"/>.
         /// </summary>
         public double Time => m_TimeSec;
 
@@ -35,13 +35,13 @@ namespace Unity.Netcode
         public float TimeAsFloat => (float)m_TimeSec;
 
         /// <summary>
-        /// Gets he current fixed network time. This is the time value of the last network tick. Similar to <see cref="Time.fixedTime"/>
+        /// Gets he current fixed network time. This is the time value of the last network tick. Similar to <see cref="Time.fixedUnscaledTime"/>.
         /// </summary>
         public double FixedTime => m_CachedTick * m_TickInterval;
 
         /// <summary>
         /// Gets the fixed delta time. This value is based on the <see cref="TickRate"/> and stays constant.
-        /// Similar to <see cref="Time.fixedDeltaTime"/> There is no equivalent to <see cref="Time.deltaTime"/>
+        /// Similar to <see cref="Time.fixedUnscaledTime"/> There is no equivalent to <see cref="Time.deltaTime"/>.
         /// </summary>
         public float FixedDeltaTime => (float)m_TickInterval;
 

Runtime/Timing/NetworkTimeSystem.cs

@@ -76,7 +76,7 @@ namespace Unity.Netcode
         }
 
         /// <summary>
-        /// Advances the time system by a certain amount of time. Should be called once per frame with Time.deltaTime or similar.
+        /// Advances the time system by a certain amount of time. Should be called once per frame with Time.unscaledDeltaTime or similar.
         /// </summary>
         /// <param name="deltaTimeSec">The amount of time to advance. The delta time which passed since Advance was last called.</param>
         /// <returns></returns>

Runtime/Transports/UNET/UNetTransport.cs

@@ -7,6 +7,7 @@ using UnityEngine.Networking;
 
 namespace Unity.Netcode.Transports.UNET
 {
+    [AddComponentMenu("Netcode/UNet Transport")]
     public class UNetTransport : NetworkTransport
     {
         public enum SendMode

Runtime/Transports/UTP/BatchedReceiveQueue.cs

@@ -1,5 +1,9 @@
 using System;
 using Unity.Networking.Transport;
+#if UTP_TRANSPORT_2_0_ABOVE
+using Unity.Collections;
+using Unity.Collections.LowLevel.Unsafe;
+#endif
 
 namespace Unity.Netcode.Transports.UTP
 {
@@ -25,7 +29,11 @@ namespace Unity.Netcode.Transports.UTP
             {
                 fixed (byte* dataPtr = m_Data)
                 {
+#if UTP_TRANSPORT_2_0_ABOVE
+                    reader.ReadBytesUnsafe(dataPtr, reader.Length);
+#else
                     reader.ReadBytes(dataPtr, reader.Length);
+#endif
                 }
             }
 
@@ -62,7 +70,11 @@ namespace Unity.Netcode.Transports.UTP
             {
                 fixed (byte* dataPtr = m_Data)
                 {
+#if UTP_TRANSPORT_2_0_ABOVE
+                    reader.ReadBytesUnsafe(dataPtr + m_Offset + m_Length, reader.Length);
+#else
                     reader.ReadBytes(dataPtr + m_Offset + m_Length, reader.Length);
+#endif
                 }
             }
 

Runtime/Transports/UTP/BatchedSendQueue.cs

@@ -8,22 +8,30 @@ namespace Unity.Netcode.Transports.UTP
     /// <summary>Queue for batched messages meant to be sent through UTP.</summary>
     /// <remarks>
     /// Messages should be pushed on the queue with <see cref="PushMessage"/>. To send batched
-    /// messages, call <see cref="FillWriter"> with the <see cref="DataStreamWriter"/> obtained from
-    /// <see cref="NetworkDriver.BeginSend"/>. This will fill the writer with as many messages as
-    /// possible. If the send is successful, call <see cref="Consume"/> to remove the data from the
-    /// queue.
+    /// messages, call <see cref="FillWriterWithMessages"/> or <see cref="FillWriterWithBytes"/>
+    /// with the <see cref="DataStreamWriter"/> obtained from <see cref="NetworkDriver.BeginSend"/>.
+    /// This will fill the writer with as many messages/bytes as possible. If the send is
+    /// successful, call <see cref="Consume"/> to remove the data from the queue.
     ///
     /// This is meant as a companion to <see cref="BatchedReceiveQueue"/>, which should be used to
     /// read messages sent with this queue.
     /// </remarks>
     internal struct BatchedSendQueue : IDisposable
     {
-        private NativeArray<byte> m_Data;
+        // Note that we're using NativeList basically like a growable NativeArray, where the length
+        // of the list is the capacity of our array. (We can't use the capacity of the list as our
+        // queue capacity because NativeList may elect to set it higher than what we'd set it to
+        // with SetCapacity, which breaks the logic of our code.)
+        private NativeList<byte> m_Data;
         private NativeArray<int> m_HeadTailIndices;
+        private int m_MaximumCapacity;
+        private int m_MinimumCapacity;
 
         /// <summary>Overhead that is added to each message in the queue.</summary>
         public const int PerMessageOverhead = sizeof(int);
 
+        internal const int MinimumMinimumCapacity = 4096;
+
         // Indices into m_HeadTailIndicies.
         private const int k_HeadInternalIndex = 0;
         private const int k_TailInternalIndex = 1;
@@ -43,18 +51,33 @@ namespace Unity.Netcode.Transports.UTP
         }
 
         public int Length => TailIndex - HeadIndex;
-
+        public int Capacity => m_Data.Length;
         public bool IsEmpty => HeadIndex == TailIndex;
-
         public bool IsCreated => m_Data.IsCreated;
 
         /// <summary>Construct a new empty send queue.</summary>
         /// <param name="capacity">Maximum capacity of the send queue.</param>
         public BatchedSendQueue(int capacity)
         {
-            m_Data = new NativeArray<byte>(capacity, Allocator.Persistent);
+            // Make sure the maximum capacity will be even.
+            m_MaximumCapacity = capacity + (capacity & 1);
+
+            // We pick the minimum capacity such that if we keep doubling it, we'll eventually hit
+            // the maximum capacity exactly. The alternative would be to use capacities that are
+            // powers of 2, but this can lead to over-allocating quite a bit of memory (especially
+            // since we expect maximum capacities to be in the megabytes range). The approach taken
+            // here avoids this issue, at the cost of not having allocations of nice round sizes.
+            m_MinimumCapacity = m_MaximumCapacity;
+            while (m_MinimumCapacity / 2 >= MinimumMinimumCapacity)
+            {
+                m_MinimumCapacity /= 2;
+            }
+
+            m_Data = new NativeList<byte>(m_MinimumCapacity, Allocator.Persistent);
             m_HeadTailIndices = new NativeArray<int>(2, Allocator.Persistent);
 
+            m_Data.ResizeUninitialized(m_MinimumCapacity);
+
             HeadIndex = 0;
             TailIndex = 0;
         }
@@ -68,18 +91,28 @@ namespace Unity.Netcode.Transports.UTP
             }
         }
 
+        /// <summary>Write a raw buffer to a DataStreamWriter.</summary>
+        private unsafe void WriteBytes(ref DataStreamWriter writer, byte* data, int length)
+        {
+#if UTP_TRANSPORT_2_0_ABOVE
+            writer.WriteBytesUnsafe(data, length);
+#else
+            writer.WriteBytes(data, length);
+#endif
+        }
+
         /// <summary>Append data at the tail of the queue. No safety checks.</summary>
         private void AppendDataAtTail(ArraySegment<byte> data)
         {
             unsafe
             {
-                var writer = new DataStreamWriter((byte*)m_Data.GetUnsafePtr() + TailIndex, m_Data.Length - TailIndex);
+                var writer = new DataStreamWriter((byte*)m_Data.GetUnsafePtr() + TailIndex, Capacity - TailIndex);
 
                 writer.WriteInt(data.Count);
 
                 fixed (byte* dataPtr = data.Array)
                 {
-                    writer.WriteBytes(dataPtr + data.Offset, data.Count);
+                    WriteBytes(ref writer, dataPtr + data.Offset, data.Count);
                 }
             }
 
@@ -100,16 +133,16 @@ namespace Unity.Netcode.Transports.UTP
             }
 
             // Check if there's enough room after the current tail index.
-            if (m_Data.Length - TailIndex >= sizeof(int) + message.Count)
+            if (Capacity - TailIndex >= sizeof(int) + message.Count)
             {
                 AppendDataAtTail(message);
                 return true;
             }
 
-            // Check if there would be enough room if we moved data at the beginning of m_Data.
-            if (m_Data.Length - TailIndex + HeadIndex >= sizeof(int) + message.Count)
+            // Move the data at the beginning of of m_Data. Either it will leave enough space for
+            // the message, or we'll grow m_Data and will want the data at the beginning anyway.
+            if (HeadIndex > 0 && Length > 0)
             {
-                // Move the data back at the beginning of m_Data.
                 unsafe
                 {
                     UnsafeUtility.MemMove(m_Data.GetUnsafePtr(), (byte*)m_Data.GetUnsafePtr() + HeadIndex, Length);
@@ -117,12 +150,38 @@ namespace Unity.Netcode.Transports.UTP
 
                 TailIndex = Length;
                 HeadIndex = 0;
+            }
 
+            // If there's enough space left at the end for the message, now is a good time to trim
+            // the capacity of m_Data if it got very large. We define "very large" here as having
+            // more than 75% of m_Data unused after adding the new message.
+            if (Capacity - TailIndex >= sizeof(int) + message.Count)
+            {
                 AppendDataAtTail(message);
+
+                while (TailIndex < Capacity / 4 && Capacity > m_MinimumCapacity)
+                {
+                    m_Data.ResizeUninitialized(Capacity / 2);
+                }
+
                 return true;
             }
 
-            return false;
+            // If we get here we need to grow m_Data until the data fits (or it's too large).
+            while (Capacity - TailIndex < sizeof(int) + message.Count)
+            {
+                // Can't grow m_Data anymore. Message simply won't fit.
+                if (Capacity * 2 > m_MaximumCapacity)
+                {
+                    return false;
+                }
+
+                m_Data.ResizeUninitialized(Capacity * 2);
+            }
+
+            // If we get here we know there's now enough room for the message.
+            AppendDataAtTail(message);
+            return true;
         }
 
         /// <summary>
@@ -149,12 +208,12 @@ namespace Unity.Netcode.Transports.UTP
 
             unsafe
             {
-                var reader = new DataStreamReader((byte*)m_Data.GetUnsafePtr() + HeadIndex, Length);
+                var reader = new DataStreamReader(m_Data.AsArray());
 
                 var writerAvailable = writer.Capacity;
-                var readerOffset = 0;
+                var readerOffset = HeadIndex;
 
-                while (readerOffset < Length)
+                while (readerOffset < TailIndex)
                 {
                     reader.SeekSet(readerOffset);
                     var messageLength = reader.ReadInt();
@@ -168,7 +227,7 @@ namespace Unity.Netcode.Transports.UTP
                         writer.WriteInt(messageLength);
 
                         var messageOffset = HeadIndex + reader.GetBytesRead();
-                        writer.WriteBytes((byte*)m_Data.GetUnsafePtr() + messageOffset, messageLength);
+                        WriteBytes(ref writer, (byte*)m_Data.GetUnsafePtr() + messageOffset, messageLength);
 
                         writerAvailable -= sizeof(int) + messageLength;
                         readerOffset += sizeof(int) + messageLength;
@@ -205,7 +264,7 @@ namespace Unity.Netcode.Transports.UTP
 
             unsafe
             {
-                writer.WriteBytes((byte*)m_Data.GetUnsafePtr() + HeadIndex, copyLength);
+                WriteBytes(ref writer, (byte*)m_Data.GetUnsafePtr() + HeadIndex, copyLength);
             }
 
             return copyLength;
@@ -219,10 +278,14 @@ namespace Unity.Netcode.Transports.UTP
         /// <param name="size">Number of bytes to consume from the queue.</param>
         public void Consume(int size)
         {
+            // Adjust the head/tail indices such that we consume the given size.
             if (size >= Length)
             {
                 HeadIndex = 0;
                 TailIndex = 0;
+
+                // This is a no-op if m_Data is already at minimum capacity.
+                m_Data.ResizeUninitialized(m_MinimumCapacity);
             }
             else
             {

Runtime/Transports/UTP/NetworkMetricsPipelineStage.cs

@@ -4,25 +4,24 @@ using AOT;
 using Unity.Burst;
 using Unity.Collections.LowLevel.Unsafe;
 using Unity.Networking.Transport;
-using UnityEngine;
 
 namespace Unity.Netcode.Transports.UTP
 {
     [BurstCompile]
     internal unsafe struct NetworkMetricsPipelineStage : INetworkPipelineStage
     {
-        static TransportFunctionPointer<NetworkPipelineStage.ReceiveDelegate> ReceiveFunction = new TransportFunctionPointer<NetworkPipelineStage.ReceiveDelegate>(Receive);
-        static TransportFunctionPointer<NetworkPipelineStage.SendDelegate> SendFunction = new TransportFunctionPointer<NetworkPipelineStage.SendDelegate>(Send);
-        static TransportFunctionPointer<NetworkPipelineStage.InitializeConnectionDelegate> InitializeConnectionFunction = new TransportFunctionPointer<NetworkPipelineStage.InitializeConnectionDelegate>(InitializeConnection);
+        private static TransportFunctionPointer<NetworkPipelineStage.ReceiveDelegate> s_ReceiveFunction = new TransportFunctionPointer<NetworkPipelineStage.ReceiveDelegate>(Receive);
+        private static TransportFunctionPointer<NetworkPipelineStage.SendDelegate> s_SendFunction = new TransportFunctionPointer<NetworkPipelineStage.SendDelegate>(Send);
+        private static TransportFunctionPointer<NetworkPipelineStage.InitializeConnectionDelegate> s_InitializeConnectionFunction = new TransportFunctionPointer<NetworkPipelineStage.InitializeConnectionDelegate>(InitializeConnection);
 
         public NetworkPipelineStage StaticInitialize(byte* staticInstanceBuffer,
             int staticInstanceBufferLength,
             NetworkSettings settings)
         {
             return new NetworkPipelineStage(
-                ReceiveFunction,
-                SendFunction,
-                InitializeConnectionFunction,
+                s_ReceiveFunction,
+                s_SendFunction,
+                s_InitializeConnectionFunction,
                 ReceiveCapacity: 0,
                 SendCapacity: 0,
                 HeaderCapacity: 0,

Runtime/Transports/UTP/SecretsLoaderHelper.cs

@@ -0,0 +1,188 @@
+using System;
+using System.IO;
+using UnityEngine;
+
+namespace Unity.Netcode.Transports.UTP
+{
+    /// <summary>
+    /// Component to add to a NetworkManager if you want the certificates to be loaded from files.
+    /// Mostly helpful to ease development and testing, especially with self-signed certificates
+    ///
+    /// Shipping code should make the calls to
+    /// - SetServerSecrets
+    /// - SetClientSecrets
+    /// directly, instead of relying on this.
+    /// </summary>
+    public class SecretsLoaderHelper : MonoBehaviour
+    {
+        internal struct ServerSecrets
+        {
+            public string ServerPrivate;
+            public string ServerCertificate;
+        };
+
+        internal struct ClientSecrets
+        {
+            public string ServerCommonName;
+            public string ClientCertificate;
+        };
+
+        private void Awake()
+        {
+            var serverSecrets = new ServerSecrets();
+
+            try
+            {
+                serverSecrets.ServerCertificate = ServerCertificate;
+            }
+            catch (Exception exception)
+            {
+                Debug.Log(exception);
+            }
+
+            try
+            {
+                serverSecrets.ServerPrivate = ServerPrivate;
+            }
+            catch (Exception exception)
+            {
+                Debug.Log(exception);
+            }
+
+            var clientSecrets = new ClientSecrets();
+            try
+            {
+                clientSecrets.ClientCertificate = ClientCA;
+            }
+            catch (Exception exception)
+            {
+                Debug.Log(exception);
+            }
+
+            try
+            {
+                clientSecrets.ServerCommonName = ServerCommonName;
+            }
+            catch (Exception exception)
+            {
+                Debug.Log(exception);
+            }
+
+            var unityTransportComponent = GetComponent<UnityTransport>();
+
+            if (unityTransportComponent == null)
+            {
+                Debug.LogError($"You need to select the UnityTransport protocol, in the NetworkManager, in order for the SecretsLoaderHelper component to be useful.");
+                return;
+            }
+
+            unityTransportComponent.SetServerSecrets(serverSecrets.ServerCertificate, serverSecrets.ServerPrivate);
+            unityTransportComponent.SetClientSecrets(clientSecrets.ServerCommonName, clientSecrets.ClientCertificate);
+        }
+
+        [Tooltip("Hostname")]
+        [SerializeField]
+        private string m_ServerCommonName = "localhost";
+
+        /// <summary>Common name of the server (typically its hostname).</summary>
+        public string ServerCommonName
+        {
+            get => m_ServerCommonName;
+            set => m_ServerCommonName = value;
+        }
+
+        [Tooltip("Client CA filepath. Useful with self-signed certificates")]
+        [SerializeField]
+        private string m_ClientCAFilePath = ""; // "Assets/Secure/myGameClientCA.pem"
+
+        /// <summary>Client CA filepath. Useful with self-signed certificates</summary>
+        public string ClientCAFilePath
+        {
+            get => m_ClientCAFilePath;
+            set => m_ClientCAFilePath = value;
+        }
+
+        [Tooltip("Client CA Override. Only useful for development with self-signed certificates. Certificate content, for platforms that lack file access (WebGL)")]
+        [SerializeField]
+        private string m_ClientCAOverride = "";
+
+        /// <summary>
+        /// Client CA Override. Only useful for development with self-signed certificates.
+        /// Certificate content, for platforms that lack file access (WebGL)
+        /// </summary>
+        public string ClientCAOverride
+        {
+            get => m_ClientCAOverride;
+            set => m_ClientCAOverride = value;
+        }
+
+        [Tooltip("Server Certificate filepath")]
+        [SerializeField]
+        private string m_ServerCertificateFilePath = ""; // "Assets/Secure/myGameServerCertificate.pem"
+
+        /// <summary>Server Certificate filepath</summary>
+        public string ServerCertificateFilePath
+        {
+            get => m_ServerCertificateFilePath;
+            set => m_ServerCertificateFilePath = value;
+        }
+
+        [Tooltip("Server Private Key filepath")]
+        [SerializeField]
+        private string m_ServerPrivateFilePath = ""; // "Assets/Secure/myGameServerPrivate.pem"
+
+        /// <summary>Server Private Key filepath</summary>
+        public string ServerPrivateFilePath
+        {
+            get => m_ServerPrivateFilePath;
+            set => m_ServerPrivate = value;
+        }
+
+        private string m_ClientCA;
+
+        /// <summary>CA certificate used by the client.</summary>
+        public string ClientCA
+        {
+            get
+            {
+                if (m_ClientCAOverride != "")
+                {
+                    return m_ClientCAOverride;
+                }
+                return ReadFile(m_ClientCAFilePath, "Client Certificate");
+            }
+            set => m_ClientCA = value;
+        }
+
+        private string m_ServerCertificate;
+
+        /// <summary>Certificate used by the server.</summary>
+        public string ServerCertificate
+        {
+            get => ReadFile(m_ServerCertificateFilePath, "Server Certificate");
+            set => m_ServerCertificate = value;
+        }
+
+        private string m_ServerPrivate;
+
+        /// <summary>Private key used by the server.</summary>
+        public string ServerPrivate
+        {
+            get => ReadFile(m_ServerPrivateFilePath, "Server Key");
+            set => m_ServerPrivate = value;
+        }
+
+        private static string ReadFile(string path, string label)
+        {
+            if (path == null || path == "")
+            {
+                return "";
+            }
+
+            var reader = new StreamReader(path);
+            string fileContent = reader.ReadToEnd();
+            Debug.Log((fileContent.Length > 1) ? ("Successfully loaded " + fileContent.Length + " byte(s) from " + label) : ("Could not read " + label + " file"));
+            return fileContent;
+        }
+    }
+}

Runtime/Transports/UTP/SecretsLoaderHelper.cs.meta

@@ -0,0 +1,11 @@
+fileFormatVersion: 2
+guid: dc1e7a8dc597cf24c95e4acf92c0edf5
+MonoImporter:
+  externalObjects: {}
+  serializedVersion: 2
+  defaultReferences: []
+  executionOrder: 0
+  icon: {instanceID: 0}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: 

Runtime/Transports/UTP/UnityTransport.cs

@@ -1,3 +1,10 @@
+// NetSim Implementation compilation boilerplate
+// All references to UNITY_MP_TOOLS_NETSIM_IMPLEMENTATION_ENABLED should be defined in the same way,
+// as any discrepancies are likely to result in build failures
+#if UNITY_EDITOR || (DEVELOPMENT_BUILD && !UNITY_MP_TOOLS_NETSIM_DISABLED_IN_DEVELOP) || (!DEVELOPMENT_BUILD && UNITY_MP_TOOLS_NETSIM_ENABLED_IN_RELEASE)
+#define UNITY_MP_TOOLS_NETSIM_IMPLEMENTATION_ENABLED
+#endif
+
 using System;
 using System.Collections.Generic;
 using UnityEngine;
@@ -8,6 +15,13 @@ using Unity.Collections;
 using Unity.Networking.Transport;
 using Unity.Networking.Transport.Relay;
 using Unity.Networking.Transport.Utilities;
+#if UTP_TRANSPORT_2_0_ABOVE
+using Unity.Networking.Transport.TLS;
+#endif
+
+#if !UTP_TRANSPORT_2_0_ABOVE
+using NetworkEndpoint = Unity.Networking.Transport.NetworkEndPoint;
+#endif
 
 namespace Unity.Netcode.Transports.UTP
 {
@@ -88,6 +102,7 @@ namespace Unity.Netcode.Transports.UTP
     /// The Netcode for GameObjects NetworkTransport for UnityTransport.
     /// Note: This is highly recommended to use over UNet.
     /// </summary>
+    [AddComponentMenu("Netcode/Unity Transport")]
     public partial class UnityTransport : NetworkTransport, INetworkStreamDriverConstructor
     {
         /// <summary>
@@ -125,8 +140,13 @@ namespace Unity.Netcode.Transports.UTP
         /// <summary>
         /// The default maximum send queue size
         /// </summary>
+        [Obsolete("MaxSendQueueSize is now determined dynamically (can still be set programmatically using the MaxSendQueueSize property). This initial value is not used anymore.", false)]
         public const int InitialMaxSendQueueSize = 16 * InitialMaxPayloadSize;
 
+        // Maximum reliable throughput, assuming the full reliable window can be sent on every
+        // frame at 60 FPS. This will be a large over-estimation in any realistic scenario.
+        private const int k_MaxReliableThroughput = (NetworkParameterConstants.MTU * 32 * 60) / 1000; // bytes per millisecond
+
         private static ConnectionAddressData s_DefaultConnectionAddressData = new ConnectionAddressData { Address = "127.0.0.1", Port = 7777, ServerListenAddress = string.Empty };
 
 #pragma warning disable IDE1006 // Naming Styles
@@ -146,6 +166,30 @@ namespace Unity.Netcode.Transports.UTP
         [SerializeField]
         private ProtocolType m_ProtocolType;
 
+#if UTP_TRANSPORT_2_0_ABOVE
+        [Tooltip("Per default the client/server will communicate over UDP. Set to true to communicate with WebSocket.")]
+        [SerializeField]
+        private bool m_UseWebSockets = false;
+
+        public bool UseWebSockets
+        {
+            get => m_UseWebSockets;
+            set => m_UseWebSockets = value;
+        }
+
+        /// <summary>
+        /// Per default the client/server communication will not be encrypted. Select true to enable DTLS for UDP and TLS for Websocket.
+        /// </summary>
+        [Tooltip("Per default the client/server communication will not be encrypted. Select true to enable DTLS for UDP and TLS for Websocket.")]
+        [SerializeField]
+        private bool m_UseEncryption = false;
+        public bool UseEncryption
+        {
+            get => m_UseEncryption;
+            set => m_UseEncryption = value;
+        }
+#endif
+
         [Tooltip("The maximum amount of packets that can be in the internal send/receive queues. Basically this is how many packets can be sent/received in a single update/frame.")]
         [SerializeField]
         private int m_MaxPacketQueueSize = InitialMaxPacketQueueSize;
@@ -158,26 +202,28 @@ namespace Unity.Netcode.Transports.UTP
             set => m_MaxPacketQueueSize = value;
         }
 
-        [Tooltip("The maximum size of a payload that can be handled by the transport.")]
+        [Tooltip("The maximum size of an unreliable payload that can be handled by the transport.")]
         [SerializeField]
         private int m_MaxPayloadSize = InitialMaxPayloadSize;
 
-        /// <summary>The maximum size of a payload that can be handled by the transport.</summary>
+        /// <summary>The maximum size of an unreliable payload that can be handled by the transport.</summary>
         public int MaxPayloadSize
         {
             get => m_MaxPayloadSize;
             set => m_MaxPayloadSize = value;
         }
 
-        [Tooltip("The maximum size in bytes of the transport send queue. The send queue accumulates messages for batching and stores messages when other internal send queues are full. If you routinely observe an error about too many in-flight packets, try increasing this.")]
-        [SerializeField]
-        private int m_MaxSendQueueSize = InitialMaxSendQueueSize;
+        private int m_MaxSendQueueSize = 0;
 
         /// <summary>The maximum size in bytes of the transport send queue.</summary>
         /// <remarks>
         /// The send queue accumulates messages for batching and stores messages when other internal
-        /// send queues are full. If you routinely observe an error about too many in-flight packets,
-        /// try increasing this.
+        /// send queues are full. Note that there should not be any need to set this value manually
+        /// since the send queue size is dynamically sized based on need.
+        ///
+        /// This value should only be set if you have particular requirements (e.g. if you want to
+        /// limit the memory usage of the send queues). Note however that setting this value too low
+        /// can easily lead to disconnections under heavy traffic.
         /// </remarks>
         public int MaxSendQueueSize
         {
@@ -263,12 +309,14 @@ namespace Unity.Netcode.Transports.UTP
             [SerializeField]
             public string ServerListenAddress;
 
-            private static NetworkEndPoint ParseNetworkEndpoint(string ip, ushort port)
+            private static NetworkEndpoint ParseNetworkEndpoint(string ip, ushort port)
             {
-                if (!NetworkEndPoint.TryParse(ip, port, out var endpoint))
+                NetworkEndpoint endpoint = default;
+
+                if (!NetworkEndpoint.TryParse(ip, port, out endpoint, NetworkFamily.Ipv4) &&
+                    !NetworkEndpoint.TryParse(ip, port, out endpoint, NetworkFamily.Ipv6))
                 {
                     Debug.LogError($"Invalid network endpoint: {ip}:{port}.");
-                    return default;
                 }
 
                 return endpoint;
@@ -277,12 +325,12 @@ namespace Unity.Netcode.Transports.UTP
             /// <summary>
             /// Endpoint (IP address and port) clients will connect to.
             /// </summary>
-            public NetworkEndPoint ServerEndPoint => ParseNetworkEndpoint(Address, Port);
+            public NetworkEndpoint ServerEndPoint => ParseNetworkEndpoint(Address, Port);
 
             /// <summary>
             /// Endpoint (IP address and port) server will listen/bind on.
             /// </summary>
-            public NetworkEndPoint ListenEndPoint => ParseNetworkEndpoint((ServerListenAddress == string.Empty) ? Address : ServerListenAddress, Port);
+            public NetworkEndpoint ListenEndPoint => ParseNetworkEndpoint((ServerListenAddress?.Length == 0) ? Address : ServerListenAddress, Port);
         }
 
         /// <summary>
@@ -326,6 +374,9 @@ namespace Unity.Netcode.Transports.UTP
         /// - packet jitter (variances in latency, see: https://en.wikipedia.org/wiki/Jitter)
         /// - packet drop rate (packet loss)
         /// </summary>
+#if UTP_TRANSPORT_2_0_ABOVE
+        [Obsolete("DebugSimulator is no longer supported and has no effect. Use Network Simulator from the Multiplayer Tools package.", false)]
+#endif
         public SimulatorParameters DebugSimulator = new SimulatorParameters
         {
             PacketDelayMS = 0,
@@ -333,6 +384,8 @@ namespace Unity.Netcode.Transports.UTP
             PacketDropRate = 0
         };
 
+        internal uint? DebugSimulatorRandomSeed { get; set; } = null;
+
         private struct PacketLossCache
         {
             public int PacketsReceived;
@@ -340,6 +393,10 @@ namespace Unity.Netcode.Transports.UTP
             public float PacketLoss;
         };
 
+        internal static event Action<int, NetworkDriver> TransportInitialized;
+        internal static event Action<int> TransportDisposed;
+        internal NetworkDriver NetworkDriver => m_Driver;
+
         private PacketLossCache m_PacketLossCache = new PacketLossCache();
 
         private State m_State = State.Disconnected;
@@ -383,6 +440,8 @@ namespace Unity.Netcode.Transports.UTP
                 out m_UnreliableFragmentedPipeline,
                 out m_UnreliableSequencedFragmentedPipeline,
                 out m_ReliableSequencedPipeline);
+
+            TransportInitialized?.Invoke(GetInstanceID(), NetworkDriver);
         }
 
         private void DisposeInternals()
@@ -400,6 +459,8 @@ namespace Unity.Netcode.Transports.UTP
             }
 
             m_SendQueue.Clear();
+
+            TransportDisposed?.Invoke(GetInstanceID());
         }
 
         private NetworkPipeline SelectSendPipeline(NetworkDelivery delivery)
@@ -425,7 +486,7 @@ namespace Unity.Netcode.Transports.UTP
 
         private bool ClientBindAndConnect()
         {
-            var serverEndpoint = default(NetworkEndPoint);
+            var serverEndpoint = default(NetworkEndpoint);
 
             if (m_ProtocolType == ProtocolType.RelayUnityTransport)
             {
@@ -438,6 +499,7 @@ namespace Unity.Netcode.Transports.UTP
                 }
 
                 m_NetworkSettings.WithRelayParameters(ref m_RelayServerData, m_HeartbeatTimeoutMS);
+                serverEndpoint = m_RelayServerData.Endpoint;
             }
             else
             {
@@ -446,7 +508,8 @@ namespace Unity.Netcode.Transports.UTP
 
             InitDriver();
 
-            int result = m_Driver.Bind(NetworkEndPoint.AnyIpv4);
+            var bindEndpoint = serverEndpoint.Family == NetworkFamily.Ipv6 ? NetworkEndpoint.AnyIpv6 : NetworkEndpoint.AnyIpv4;
+            int result = m_Driver.Bind(bindEndpoint);
             if (result != 0)
             {
                 Debug.LogError("Client failed to bind");
@@ -459,7 +522,7 @@ namespace Unity.Netcode.Transports.UTP
             return true;
         }
 
-        private bool ServerBindAndListen(NetworkEndPoint endPoint)
+        private bool ServerBindAndListen(NetworkEndpoint endPoint)
         {
             InitDriver();
 
@@ -481,51 +544,13 @@ namespace Unity.Netcode.Transports.UTP
             return true;
         }
 
-        private static RelayAllocationId ConvertFromAllocationIdBytes(byte[] allocationIdBytes)
-        {
-            unsafe
-            {
-                fixed (byte* ptr = allocationIdBytes)
-                {
-                    return RelayAllocationId.FromBytePointer(ptr, allocationIdBytes.Length);
-                }
-            }
-        }
-
-        private static RelayHMACKey ConvertFromHMAC(byte[] hmac)
-        {
-            unsafe
-            {
-                fixed (byte* ptr = hmac)
-                {
-                    return RelayHMACKey.FromBytePointer(ptr, RelayHMACKey.k_Length);
-                }
-            }
-        }
-
-        private static RelayConnectionData ConvertConnectionData(byte[] connectionData)
-        {
-            unsafe
-            {
-                fixed (byte* ptr = connectionData)
-                {
-                    return RelayConnectionData.FromBytePointer(ptr, RelayConnectionData.k_Length);
-                }
-            }
-        }
-
-        internal void SetMaxPayloadSize(int maxPayloadSize)
-        {
-            m_MaxPayloadSize = maxPayloadSize;
-        }
-
         private void SetProtocol(ProtocolType inProtocol)
         {
             m_ProtocolType = inProtocol;
         }
 
         /// <summary>Set the relay server data for the server.</summary>
-        /// <param name="ipv4Address">IP address of the relay server.</param>
+        /// <param name="ipv4Address">IP address or hostname of the relay server.</param>
         /// <param name="port">UDP port of the relay server.</param>
         /// <param name="allocationIdBytes">Allocation ID as a byte array.</param>
         /// <param name="keyBytes">Allocation key as a byte array.</param>
@@ -534,39 +559,21 @@ namespace Unity.Netcode.Transports.UTP
         /// <param name="isSecure">Whether the connection is secure (uses DTLS).</param>
         public void SetRelayServerData(string ipv4Address, ushort port, byte[] allocationIdBytes, byte[] keyBytes, byte[] connectionDataBytes, byte[] hostConnectionDataBytes = null, bool isSecure = false)
         {
-            RelayConnectionData hostConnectionData;
-
-            if (!NetworkEndPoint.TryParse(ipv4Address, port, out var serverEndpoint))
-            {
-                Debug.LogError($"Invalid address {ipv4Address}:{port}");
-
-                // We set this to default to cause other checks to fail to state you need to call this
-                // function again.
-                m_RelayServerData = default;
-                return;
-            }
-
-            var allocationId = ConvertFromAllocationIdBytes(allocationIdBytes);
-            var key = ConvertFromHMAC(keyBytes);
-            var connectionData = ConvertConnectionData(connectionDataBytes);
-
-            if (hostConnectionDataBytes != null)
-            {
-                hostConnectionData = ConvertConnectionData(hostConnectionDataBytes);
-            }
-            else
-            {
-                hostConnectionData = connectionData;
-            }
-
-            m_RelayServerData = new RelayServerData(ref serverEndpoint, 0, ref allocationId, ref connectionData, ref hostConnectionData, ref key, isSecure);
-            m_RelayServerData.ComputeNewNonce();
+            var hostConnectionData = hostConnectionDataBytes ?? connectionDataBytes;
+            m_RelayServerData = new RelayServerData(ipv4Address, port, allocationIdBytes, connectionDataBytes, hostConnectionData, keyBytes, isSecure);
+            SetProtocol(ProtocolType.RelayUnityTransport);
+        }
 
+        /// <summary>Set the relay server data (using the lower-level Unity Transport data structure).</summary>
+        /// <param name="serverData">Data for the Relay server to use.</param>
+        public void SetRelayServerData(RelayServerData serverData)
+        {
+            m_RelayServerData = serverData;
             SetProtocol(ProtocolType.RelayUnityTransport);
         }
 
         /// <summary>Set the relay server data for the host.</summary>
-        /// <param name="ipAddress">IP address of the relay server.</param>
+        /// <param name="ipAddress">IP address or hostname of the relay server.</param>
         /// <param name="port">UDP port of the relay server.</param>
         /// <param name="allocationId">Allocation ID as a byte array.</param>
         /// <param name="key">Allocation key as a byte array.</param>
@@ -578,7 +585,7 @@ namespace Unity.Netcode.Transports.UTP
         }
 
         /// <summary>Set the relay server data for the host.</summary>
-        /// <param name="ipAddress">IP address of the relay server.</param>
+        /// <param name="ipAddress">IP address or hostname of the relay server.</param>
         /// <param name="port">UDP port of the relay server.</param>
         /// <param name="allocationId">Allocation ID as a byte array.</param>
         /// <param name="key">Allocation key as a byte array.</param>
@@ -593,7 +600,7 @@ namespace Unity.Netcode.Transports.UTP
         /// <summary>
         /// Sets IP and Port information. This will be ignored if using the Unity Relay and you should call <see cref="SetRelayServerData"/>
         /// </summary>
-        /// <param name="ipv4Address">The remote IP address</param>
+        /// <param name="ipv4Address">The remote IP address (despite the name, can be an IPv6 address)</param>
         /// <param name="port">The remote port</param>
         /// <param name="listenAddress">The local listen address</param>
         public void SetConnectionData(string ipv4Address, ushort port, string listenAddress = null)
@@ -613,7 +620,7 @@ namespace Unity.Netcode.Transports.UTP
         /// </summary>
         /// <param name="endPoint">The remote end point</param>
         /// <param name="listenEndPoint">The local listen endpoint</param>
-        public void SetConnectionData(NetworkEndPoint endPoint, NetworkEndPoint listenEndPoint = default)
+        public void SetConnectionData(NetworkEndpoint endPoint, NetworkEndpoint listenEndPoint = default)
         {
             string serverAddress = endPoint.Address.Split(':')[0];
 
@@ -634,6 +641,9 @@ namespace Unity.Netcode.Transports.UTP
         /// <param name="packetDelay">Packet delay in milliseconds.</param>
         /// <param name="packetJitter">Packet jitter in milliseconds.</param>
         /// <param name="dropRate">Packet drop percentage.</param>
+#if UTP_TRANSPORT_2_0_ABOVE
+        [Obsolete("SetDebugSimulatorParameters is no longer supported and has no effect. Use Network Simulator from the Multiplayer Tools package.", false)]
+#endif
         public void SetDebugSimulatorParameters(int packetDelay, int packetJitter, int dropRate)
         {
             if (m_Driver.IsCreated)
@@ -662,7 +672,7 @@ namespace Unity.Netcode.Transports.UTP
             else
             {
                 m_NetworkSettings.WithRelayParameters(ref m_RelayServerData, m_HeartbeatTimeoutMS);
-                return ServerBindAndListen(NetworkEndPoint.AnyIpv4);
+                return ServerBindAndListen(NetworkEndpoint.AnyIpv4);
             }
         }
 
@@ -891,7 +901,7 @@ namespace Unity.Netcode.Transports.UTP
 
         private void ExtractNetworkMetricsForClient(ulong transportClientId)
         {
-            var networkConnection =  ParseClientId(transportClientId);
+            var networkConnection = ParseClientId(transportClientId);
             ExtractNetworkMetricsFromPipeline(m_UnreliableFragmentedPipeline, networkConnection);
             ExtractNetworkMetricsFromPipeline(m_UnreliableSequencedFragmentedPipeline, networkConnection);
             ExtractNetworkMetricsFromPipeline(m_ReliableSequencedPipeline, networkConnection);
@@ -907,7 +917,11 @@ namespace Unity.Netcode.Transports.UTP
         {
             //Don't need to dispose of the buffers, they are filled with data pointers.
             m_Driver.GetPipelineBuffers(pipeline,
+#if UTP_TRANSPORT_2_0_ABOVE
+                NetworkPipelineStageId.Get<NetworkMetricsPipelineStage>(),
+#else
                 NetworkPipelineStageCollection.GetStageId(typeof(NetworkMetricsPipelineStage)),
+#endif
                 networkConnection,
                 out _,
                 out _,
@@ -934,7 +948,11 @@ namespace Unity.Netcode.Transports.UTP
             }
 
             m_Driver.GetPipelineBuffers(m_ReliableSequencedPipeline,
+#if UTP_TRANSPORT_2_0_ABOVE
+                NetworkPipelineStageId.Get<ReliableSequencedPipelineStage>(),
+#else
                 NetworkPipelineStageCollection.GetStageId(typeof(ReliableSequencedPipelineStage)),
+#endif
                 networkConnection,
                 out _,
                 out _,
@@ -956,7 +974,11 @@ namespace Unity.Netcode.Transports.UTP
             }
 
             m_Driver.GetPipelineBuffers(m_ReliableSequencedPipeline,
+#if UTP_TRANSPORT_2_0_ABOVE
+                NetworkPipelineStageId.Get<ReliableSequencedPipelineStage>(),
+#else
                 NetworkPipelineStageCollection.GetStageId(typeof(ReliableSequencedPipelineStage)),
+#endif
                 networkConnection,
                 out _,
                 out _,
@@ -1117,11 +1139,12 @@ namespace Unity.Netcode.Transports.UTP
             // account for the overhead of its length when we store it in the send queue.
             var fragmentationCapacity = m_MaxPayloadSize + BatchedSendQueue.PerMessageOverhead;
 
-            m_NetworkSettings
-                .WithFragmentationStageParameters(payloadCapacity: fragmentationCapacity)
-                .WithBaselibNetworkInterfaceParameters(
-                    receiveQueueCapacity: m_MaxPacketQueueSize,
-                    sendQueueCapacity: m_MaxPacketQueueSize);
+            m_NetworkSettings.WithFragmentationStageParameters(payloadCapacity: fragmentationCapacity);
+#if !UTP_TRANSPORT_2_0_ABOVE
+            m_NetworkSettings.WithBaselibNetworkInterfaceParameters(
+                receiveQueueCapacity: m_MaxPacketQueueSize,
+                sendQueueCapacity: m_MaxPacketQueueSize);
+#endif
 #endif
         }
 
@@ -1148,18 +1171,34 @@ namespace Unity.Netcode.Transports.UTP
         /// <param name="networkDelivery">The delivery type (QoS) to send data with</param>
         public override void Send(ulong clientId, ArraySegment<byte> payload, NetworkDelivery networkDelivery)
         {
-            if (payload.Count > m_MaxPayloadSize)
+            var pipeline = SelectSendPipeline(networkDelivery);
+
+            if (pipeline != m_ReliableSequencedPipeline && payload.Count > m_MaxPayloadSize)
             {
-                Debug.LogError($"Payload of size {payload.Count} larger than configured 'Max Payload Size' ({m_MaxPayloadSize}).");
+                Debug.LogError($"Unreliable payload of size {payload.Count} larger than configured 'Max Payload Size' ({m_MaxPayloadSize}).");
                 return;
             }
 
-            var pipeline = SelectSendPipeline(networkDelivery);
-
             var sendTarget = new SendTarget(clientId, pipeline);
             if (!m_SendQueue.TryGetValue(sendTarget, out var queue))
             {
-                queue = new BatchedSendQueue(Math.Max(m_MaxSendQueueSize, m_MaxPayloadSize));
+                // The maximum size of a send queue is determined according to the disconnection
+                // timeout. The idea being that if the send queue contains enough reliable data that
+                // sending it all out would take longer than the disconnection timeout, then there's
+                // no point storing even more in the queue (it would be like having a ping higher
+                // than the disconnection timeout, which is far into the realm of unplayability).
+                //
+                // The throughput used to determine what consists the maximum send queue size is
+                // the maximum theoritical throughput of the reliable pipeline assuming we only send
+                // on each update at 60 FPS, which turns out to be around 2.688 MB/s.
+                //
+                // Note that we only care about reliable throughput for send queues because that's
+                // the only case where a full send queue causes a connection loss. Full unreliable
+                // send queues are dealt with by flushing it out to the network or simply dropping
+                // new messages if that fails.
+                var maxCapacity = m_MaxSendQueueSize > 0 ? m_MaxSendQueueSize : m_DisconnectTimeoutMS * k_MaxReliableThroughput;
+
+                queue = new BatchedSendQueue(Math.Max(maxCapacity, m_MaxPayloadSize));
                 m_SendQueue.Add(sendTarget, queue);
             }
 
@@ -1173,8 +1212,7 @@ namespace Unity.Netcode.Transports.UTP
 
                     var ngoClientId = NetworkManager?.TransportIdToClientId(clientId) ?? clientId;
                     Debug.LogError($"Couldn't add payload of size {payload.Count} to reliable send queue. " +
-                        $"Closing connection {ngoClientId} as reliability guarantees can't be maintained. " +
-                        $"Perhaps 'Max Send Queue Size' ({m_MaxSendQueueSize}) is too small for workload.");
+                        $"Closing connection {ngoClientId} as reliability guarantees can't be maintained.");
 
                     if (clientId == m_ServerClientId)
                     {
@@ -1223,9 +1261,9 @@ namespace Unity.Netcode.Transports.UTP
             }
 
             var succeeded = ClientBindAndConnect();
-            if (!succeeded)
+            if (!succeeded && m_Driver.IsCreated)
             {
-                Shutdown();
+                m_Driver.Dispose();
             }
             return succeeded;
         }
@@ -1250,16 +1288,16 @@ namespace Unity.Netcode.Transports.UTP
             {
                 case ProtocolType.UnityTransport:
                     succeeded = ServerBindAndListen(ConnectionData.ListenEndPoint);
-                    if (!succeeded)
+                    if (!succeeded && m_Driver.IsCreated)
                     {
-                        Shutdown();
+                        m_Driver.Dispose();
                     }
                     return succeeded;
                 case ProtocolType.RelayUnityTransport:
                     succeeded = StartRelayServer();
-                    if (!succeeded)
+                    if (!succeeded && m_Driver.IsCreated)
                     {
-                        Shutdown();
+                        m_Driver.Dispose();
                     }
                     return succeeded;
                 default:
@@ -1285,10 +1323,10 @@ namespace Unity.Netcode.Transports.UTP
                 SendBatchedMessages(kvp.Key, kvp.Value);
             }
 
-            // The above flush only puts the message in UTP internal buffers, need the flush send
-            // job to execute to actually get things out on the wire. This will also ensure any
-            // disconnect messages are sent out.
-            m_Driver.ScheduleFlushSend(default).Complete();
+            // The above flush only puts the message in UTP internal buffers, need an update to
+            // actually get the messages on the wire. (Normally a flush send would be sufficient,
+            // but there might be disconnect messages and those require an update call.)
+            m_Driver.ScheduleUpdate().Complete();
 
             DisposeInternals();
 
@@ -1298,16 +1336,65 @@ namespace Unity.Netcode.Transports.UTP
             m_ServerClientId = 0;
         }
 
-        private void ConfigureSimulator()
+#if UTP_TRANSPORT_2_0_ABOVE
+        private void ConfigureSimulatorForUtp2()
+        {
+            // As DebugSimulator is deprecated, the 'packetDelayMs', 'packetJitterMs' and 'packetDropPercentage'
+            // parameters are set to the default and are supposed to be changed using Network Simulator tool instead.
+            m_NetworkSettings.WithSimulatorStageParameters(
+                maxPacketCount: 300, // TODO Is there any way to compute a better value?
+                maxPacketSize: NetworkParameterConstants.MTU,
+                packetDelayMs: 0,
+                packetJitterMs: 0,
+                packetDropPercentage: 0,
+                randomSeed: DebugSimulatorRandomSeed ?? (uint)System.Diagnostics.Stopwatch.GetTimestamp()
+                , mode: ApplyMode.AllPackets
+            );
+
+            m_NetworkSettings.WithNetworkSimulatorParameters();
+        }
+#else
+        private void ConfigureSimulatorForUtp1()
         {
             m_NetworkSettings.WithSimulatorStageParameters(
                 maxPacketCount: 300, // TODO Is there any way to compute a better value?
                 maxPacketSize: NetworkParameterConstants.MTU,
                 packetDelayMs: DebugSimulator.PacketDelayMS,
                 packetJitterMs: DebugSimulator.PacketJitterMS,
-                packetDropPercentage: DebugSimulator.PacketDropRate
+                packetDropPercentage: DebugSimulator.PacketDropRate,
+                randomSeed: DebugSimulatorRandomSeed ?? (uint)System.Diagnostics.Stopwatch.GetTimestamp()
             );
         }
+#endif
+
+        private string m_ServerPrivateKey;
+        private string m_ServerCertificate;
+
+        private string m_ServerCommonName;
+        private string m_ClientCaCertificate;
+
+        /// <summary>Set the server parameters for encryption.</summary>
+        /// <param name="serverCertificate">Public certificate for the server (PEM format).</param>
+        /// <param name="serverPrivateKey">Private key for the server (PEM format).</param>
+        public void SetServerSecrets(string serverCertificate, string serverPrivateKey)
+        {
+            m_ServerPrivateKey = serverPrivateKey;
+            m_ServerCertificate = serverCertificate;
+        }
+
+        /// <summary>Set the client parameters for encryption.</summary>
+        /// <remarks>
+        /// If the CA certificate is not provided, validation will be done against the OS/browser
+        /// certificate store. This is what you'd want if using certificates from a known provider.
+        /// For self-signed certificates, the CA certificate needs to be provided.
+        /// </remarks>
+        /// <param name="serverCommonName">Common name of the server (typically hostname).</param>
+        /// <param name="caCertificate">CA certificate used to validate the server's authenticity.</param>
+        public void SetClientSecrets(string serverCommonName, string caCertificate = null)
+        {
+            m_ServerCommonName = serverCommonName;
+            m_ClientCaCertificate = caCertificate;
+        }
 
         /// <summary>
         /// Creates the internal NetworkDriver
@@ -1322,25 +1409,124 @@ namespace Unity.Netcode.Transports.UTP
             out NetworkPipeline unreliableSequencedFragmentedPipeline,
             out NetworkPipeline reliableSequencedPipeline)
         {
-#if MULTIPLAYER_TOOLS_1_0_0_PRE_7
+#if MULTIPLAYER_TOOLS_1_0_0_PRE_7 && !UTP_TRANSPORT_2_0_ABOVE
             NetworkPipelineStageCollection.RegisterPipelineStage(new NetworkMetricsPipelineStage());
 #endif
-            var maxFrameTimeMS = 0;
 
-#if UNITY_EDITOR || DEVELOPMENT_BUILD
-            maxFrameTimeMS = 100;
-            ConfigureSimulator();
+#if UTP_TRANSPORT_2_0_ABOVE && UNITY_MP_TOOLS_NETSIM_IMPLEMENTATION_ENABLED
+            ConfigureSimulatorForUtp2();
+#elif !UTP_TRANSPORT_2_0_ABOVE && (UNITY_EDITOR || DEVELOPMENT_BUILD)
+            ConfigureSimulatorForUtp1();
 #endif
 
             m_NetworkSettings.WithNetworkConfigParameters(
                 maxConnectAttempts: transport.m_MaxConnectAttempts,
                 connectTimeoutMS: transport.m_ConnectTimeoutMS,
                 disconnectTimeoutMS: transport.m_DisconnectTimeoutMS,
-                heartbeatTimeoutMS: transport.m_HeartbeatTimeoutMS,
-                maxFrameTimeMS: maxFrameTimeMS);
+#if UTP_TRANSPORT_2_0_ABOVE
+                sendQueueCapacity: m_MaxPacketQueueSize,
+                receiveQueueCapacity: m_MaxPacketQueueSize,
+#endif
+                heartbeatTimeoutMS: transport.m_HeartbeatTimeoutMS);
 
+#if UNITY_WEBGL && !UNITY_EDITOR
+            if (NetworkManager.IsServer)
+            {
+                throw new Exception("WebGL as a server is not supported by Unity Transport, outside the Editor.");
+            }
+#endif
+
+#if UTP_TRANSPORT_2_0_ABOVE
+            if (m_UseEncryption)
+            {
+                if (m_ProtocolType == ProtocolType.RelayUnityTransport)
+                {
+                    if (m_RelayServerData.IsSecure != 0)
+                    {
+                        // log an error because we have mismatched configuration
+                        Debug.LogError("Mismatched security configuration, between Relay and local NetworkManager settings");
+                    }
+
+                    // No need to to anything else if using Relay because UTP will handle the
+                    // configuration of the security parameters on its own.
+                }
+                else
+                {
+                    try
+                    {
+                        if (NetworkManager.IsServer)
+                        {
+                            if (m_ServerCertificate.Length == 0 || m_ServerPrivateKey.Length == 0)
+                            {
+                                throw new Exception("In order to use encrypted communications, when hosting, you must set the server certificate and key.");
+                            }
+                            m_NetworkSettings.WithSecureServerParameters(m_ServerCertificate, m_ServerPrivateKey);
+                        }
+                        else
+                        {
+                            if (m_ServerCommonName.Length == 0)
+                            {
+                                throw new Exception("In order to use encrypted communications, clients must set the server common name.");
+                            }
+                            else if (m_ClientCaCertificate == null)
+                            {
+                                m_NetworkSettings.WithSecureClientParameters(m_ServerCommonName);
+                            }
+                            else
+                            {
+                                m_NetworkSettings.WithSecureClientParameters(m_ClientCaCertificate, m_ServerCommonName);
+                            }
+                        }
+                    }
+                    catch(Exception e)
+                    {
+                        Debug.LogException(e, this);
+                    }
+                }
+            }
+#endif
+
+#if UTP_TRANSPORT_2_0_ABOVE
+            if (m_UseWebSockets)
+            {
+                driver = NetworkDriver.Create(new WebSocketNetworkInterface(), m_NetworkSettings);
+            }
+            else
+            {
+#if UNITY_WEBGL
+                Debug.LogWarning($"WebSockets were used even though they're not selected in NetworkManager. You should check {nameof(UseWebSockets)}', on the Unity Transport component, to silence this warning.");
+                driver = NetworkDriver.Create(new WebSocketNetworkInterface(), m_NetworkSettings);
+#else
+                driver = NetworkDriver.Create(new UDPNetworkInterface(), m_NetworkSettings);
+#endif
+            }
+#else
             driver = NetworkDriver.Create(m_NetworkSettings);
+#endif
 
+#if MULTIPLAYER_TOOLS_1_0_0_PRE_7 && UTP_TRANSPORT_2_0_ABOVE
+            driver.RegisterPipelineStage(new NetworkMetricsPipelineStage());
+#endif
+
+#if !UTP_TRANSPORT_2_0_ABOVE
+            SetupPipelinesForUtp1(driver,
+                out unreliableFragmentedPipeline,
+                out unreliableSequencedFragmentedPipeline,
+                out reliableSequencedPipeline);
+#else
+            SetupPipelinesForUtp2(driver,
+                out unreliableFragmentedPipeline,
+                out unreliableSequencedFragmentedPipeline,
+                out reliableSequencedPipeline);
+#endif
+        }
+
+#if !UTP_TRANSPORT_2_0_ABOVE
+        private void SetupPipelinesForUtp1(NetworkDriver driver,
+            out NetworkPipeline unreliableFragmentedPipeline,
+            out NetworkPipeline unreliableSequencedFragmentedPipeline,
+            out NetworkPipeline reliableSequencedPipeline)
+        {
 #if UNITY_EDITOR || DEVELOPMENT_BUILD
             if (DebugSimulator.PacketDelayMS > 0 || DebugSimulator.PacketDropRate > 0)
             {
@@ -1358,7 +1544,7 @@ namespace Unity.Netcode.Transports.UTP
                     typeof(SimulatorPipelineStage),
                     typeof(SimulatorPipelineStageInSend)
 #if MULTIPLAYER_TOOLS_1_0_0_PRE_7
-                    ,typeof(NetworkMetricsPipelineStage)
+                    , typeof(NetworkMetricsPipelineStage)
 #endif
                 );
                 reliableSequencedPipeline = driver.CreatePipeline(
@@ -1366,7 +1552,7 @@ namespace Unity.Netcode.Transports.UTP
                     typeof(SimulatorPipelineStage),
                     typeof(SimulatorPipelineStageInSend)
 #if MULTIPLAYER_TOOLS_1_0_0_PRE_7
-                    ,typeof(NetworkMetricsPipelineStage)
+                    , typeof(NetworkMetricsPipelineStage)
 #endif
                 );
             }
@@ -1376,25 +1562,63 @@ namespace Unity.Netcode.Transports.UTP
                 unreliableFragmentedPipeline = driver.CreatePipeline(
                     typeof(FragmentationPipelineStage)
 #if MULTIPLAYER_TOOLS_1_0_0_PRE_7
-                    ,typeof(NetworkMetricsPipelineStage)
+                    , typeof(NetworkMetricsPipelineStage)
 #endif
                 );
                 unreliableSequencedFragmentedPipeline = driver.CreatePipeline(
                     typeof(FragmentationPipelineStage),
                     typeof(UnreliableSequencedPipelineStage)
 #if MULTIPLAYER_TOOLS_1_0_0_PRE_7
-                    ,typeof(NetworkMetricsPipelineStage)
+                    , typeof(NetworkMetricsPipelineStage)
 #endif
                 );
                 reliableSequencedPipeline = driver.CreatePipeline(
                     typeof(ReliableSequencedPipelineStage)
 #if MULTIPLAYER_TOOLS_1_0_0_PRE_7
-                    ,typeof(NetworkMetricsPipelineStage)
+                    , typeof(NetworkMetricsPipelineStage)
 #endif
                 );
             }
         }
+#else
+        private void SetupPipelinesForUtp2(NetworkDriver driver,
+            out NetworkPipeline unreliableFragmentedPipeline,
+            out NetworkPipeline unreliableSequencedFragmentedPipeline,
+            out NetworkPipeline reliableSequencedPipeline)
+        {
 
+            unreliableFragmentedPipeline = driver.CreatePipeline(
+                typeof(FragmentationPipelineStage)
+#if UNITY_MP_TOOLS_NETSIM_IMPLEMENTATION_ENABLED
+                , typeof(SimulatorPipelineStage)
+#endif
+#if MULTIPLAYER_TOOLS_1_0_0_PRE_7
+                , typeof(NetworkMetricsPipelineStage)
+#endif
+            );
+
+            unreliableSequencedFragmentedPipeline = driver.CreatePipeline(
+                typeof(FragmentationPipelineStage),
+                typeof(UnreliableSequencedPipelineStage)
+#if UNITY_MP_TOOLS_NETSIM_IMPLEMENTATION_ENABLED
+                , typeof(SimulatorPipelineStage)
+#endif
+#if MULTIPLAYER_TOOLS_1_0_0_PRE_7
+                , typeof(NetworkMetricsPipelineStage)
+#endif
+            );
+
+            reliableSequencedPipeline = driver.CreatePipeline(
+                typeof(ReliableSequencedPipelineStage)
+#if UNITY_MP_TOOLS_NETSIM_IMPLEMENTATION_ENABLED
+                , typeof(SimulatorPipelineStage)
+#endif
+#if MULTIPLAYER_TOOLS_1_0_0_PRE_7
+                , typeof(NetworkMetricsPipelineStage)
+#endif
+            );
+        }
+#endif
         // -------------- Utility Types -------------------------------------------------------------------------------
 
 

Runtime/com.unity.netcode.runtime.asmdef

@@ -30,6 +30,11 @@
             "name": "com.unity.multiplayer.tools",
             "expression": "1.0.0-pre.7",
             "define": "MULTIPLAYER_TOOLS_1_0_0_PRE_7"
+        },
+        {
+            "name": "com.unity.transport",
+            "expression": "2.0.0-exp",
+            "define": "UTP_TRANSPORT_2_0_ABOVE"
         }
     ]
 }

TestHelpers/Runtime/IntegrationTestSceneHandler.cs

@@ -48,7 +48,7 @@ namespace Unity.Netcode.TestHelpers.Runtime
             public JobTypes JobType;
             public string SceneName;
             public Scene Scene;
-            public ISceneManagerHandler.SceneEventAction SceneAction;
+            public SceneEventProgress SceneEventProgress;
             public IntegrationTestSceneHandler IntegrationTestSceneHandler;
         }
 
@@ -106,7 +106,8 @@ namespace Unity.Netcode.TestHelpers.Runtime
 
             SceneManager.sceneLoaded += SceneManager_sceneLoaded;
             // We always load additively for all scenes during integration tests
-            SceneManager.LoadSceneAsync(queuedSceneJob.SceneName, LoadSceneMode.Additive);
+            var asyncOperation = SceneManager.LoadSceneAsync(queuedSceneJob.SceneName, LoadSceneMode.Additive);
+            queuedSceneJob.SceneEventProgress.SetAsyncOperation(asyncOperation);
 
             // Wait for it to finish
             while (queuedSceneJob.JobType != QueuedSceneJob.JobTypes.Completed)
@@ -114,7 +115,6 @@ namespace Unity.Netcode.TestHelpers.Runtime
                 yield return s_WaitForSeconds;
             }
             yield return s_WaitForSeconds;
-            CurrentQueuedSceneJob.SceneAction.Invoke();
         }
 
         /// <summary>
@@ -176,7 +176,8 @@ namespace Unity.Netcode.TestHelpers.Runtime
             SceneManager.sceneUnloaded += SceneManager_sceneUnloaded;
             if (queuedSceneJob.Scene.IsValid() && queuedSceneJob.Scene.isLoaded && !queuedSceneJob.Scene.name.Contains(NetcodeIntegrationTestHelpers.FirstPartOfTestRunnerSceneName))
             {
-                SceneManager.UnloadSceneAsync(queuedSceneJob.Scene);
+                var asyncOperation = SceneManager.UnloadSceneAsync(queuedSceneJob.Scene);
+                queuedSceneJob.SceneEventProgress.SetAsyncOperation(asyncOperation);
             }
             else
             {
@@ -188,7 +189,6 @@ namespace Unity.Netcode.TestHelpers.Runtime
             {
                 yield return s_WaitForSeconds;
             }
-            CurrentQueuedSceneJob.SceneAction.Invoke();
         }
 
         /// <summary>
@@ -246,7 +246,7 @@ namespace Unity.Netcode.TestHelpers.Runtime
         /// <summary>
         /// Server always loads like it normally would
         /// </summary>
-        public AsyncOperation GenericLoadSceneAsync(string sceneName, LoadSceneMode loadSceneMode, ISceneManagerHandler.SceneEventAction sceneEventAction)
+        public AsyncOperation GenericLoadSceneAsync(string sceneName, LoadSceneMode loadSceneMode, SceneEventProgress sceneEventProgress)
         {
             m_ServerSceneBeingLoaded = sceneName;
             if (NetcodeIntegrationTest.IsRunning)
@@ -254,8 +254,7 @@ namespace Unity.Netcode.TestHelpers.Runtime
                 SceneManager.sceneLoaded += Sever_SceneLoaded;
             }
             var operation = SceneManager.LoadSceneAsync(sceneName, loadSceneMode);
-
-            operation.completed += new Action<AsyncOperation>(asyncOp2 => { sceneEventAction.Invoke(); });
+            sceneEventProgress.SetAsyncOperation(operation);
             return operation;
         }
 
@@ -271,39 +270,39 @@ namespace Unity.Netcode.TestHelpers.Runtime
         /// <summary>
         /// Server always unloads like it normally would
         /// </summary>
-        public AsyncOperation GenericUnloadSceneAsync(Scene scene, ISceneManagerHandler.SceneEventAction sceneEventAction)
+        public AsyncOperation GenericUnloadSceneAsync(Scene scene, SceneEventProgress sceneEventProgress)
         {
             var operation = SceneManager.UnloadSceneAsync(scene);
-            operation.completed += new Action<AsyncOperation>(asyncOp2 => { sceneEventAction.Invoke(); });
+            sceneEventProgress.SetAsyncOperation(operation);
             return operation;
         }
 
 
-        public AsyncOperation LoadSceneAsync(string sceneName, LoadSceneMode loadSceneMode, ISceneManagerHandler.SceneEventAction sceneEventAction)
+        public AsyncOperation LoadSceneAsync(string sceneName, LoadSceneMode loadSceneMode, SceneEventProgress sceneEventProgress)
         {
             // Server and non NetcodeIntegrationTest tests use the generic load scene method
             if (!NetcodeIntegrationTest.IsRunning)
             {
-                return GenericLoadSceneAsync(sceneName, loadSceneMode, sceneEventAction);
+                return GenericLoadSceneAsync(sceneName, loadSceneMode, sceneEventProgress);
             }
             else // NetcodeIntegrationTest Clients always get added to the jobs queue
             {
-                AddJobToQueue(new QueuedSceneJob() { IntegrationTestSceneHandler = this, SceneName = sceneName, SceneAction = sceneEventAction, JobType = QueuedSceneJob.JobTypes.Loading });
+                AddJobToQueue(new QueuedSceneJob() { IntegrationTestSceneHandler = this, SceneName = sceneName, SceneEventProgress = sceneEventProgress, JobType = QueuedSceneJob.JobTypes.Loading });
             }
 
             return null;
         }
 
-        public AsyncOperation UnloadSceneAsync(Scene scene, ISceneManagerHandler.SceneEventAction sceneEventAction)
+        public AsyncOperation UnloadSceneAsync(Scene scene, SceneEventProgress sceneEventProgress)
         {
             // Server and non NetcodeIntegrationTest tests use the generic unload scene method
             if (!NetcodeIntegrationTest.IsRunning)
             {
-                return GenericUnloadSceneAsync(scene, sceneEventAction);
+                return GenericUnloadSceneAsync(scene, sceneEventProgress);
             }
             else // NetcodeIntegrationTest Clients always get added to the jobs queue
             {
-                AddJobToQueue(new QueuedSceneJob() { IntegrationTestSceneHandler = this, Scene = scene, SceneAction = sceneEventAction, JobType = QueuedSceneJob.JobTypes.Unloading });
+                AddJobToQueue(new QueuedSceneJob() { IntegrationTestSceneHandler = this, Scene = scene, SceneEventProgress = sceneEventProgress, JobType = QueuedSceneJob.JobTypes.Unloading });
             }
             // This is OK to return a "nothing" AsyncOperation since we are simulating client loading
             return null;

TestHelpers/Runtime/MessageHooks.cs

@@ -4,14 +4,22 @@ namespace Unity.Netcode.TestHelpers.Runtime
 {
     internal class MessageHooks : INetworkHooks
     {
-        public bool IsWaiting;
-        public delegate bool MessageReceiptCheck(object receivedMessage);
+        public bool IsWaiting = true;
+        public delegate bool MessageReceiptCheck(Type receivedMessageType);
         public MessageReceiptCheck ReceiptCheck;
+        public delegate bool MessageHandleCheck(object receivedMessage);
+        public MessageHandleCheck HandleCheck;
 
-        public static bool CheckForMessageOfType<T>(object receivedMessage) where T : INetworkMessage
+        public static bool CurrentMessageHasTriggerdAHook = false;
+
+        public static bool CheckForMessageOfTypeHandled<T>(object receivedMessage) where T : INetworkMessage
         {
             return receivedMessage is T;
         }
+        public static bool CheckForMessageOfTypeReceived<T>(Type receivedMessageType) where T : INetworkMessage
+        {
+            return receivedMessageType == typeof(T);
+        }
 
         public void OnBeforeSendMessage<T>(ulong clientId, ref T message, NetworkDelivery delivery) where T : INetworkMessage
         {
@@ -23,10 +31,24 @@ namespace Unity.Netcode.TestHelpers.Runtime
 
         public void OnBeforeReceiveMessage(ulong senderId, Type messageType, int messageSizeBytes)
         {
+            // The way the system works, it goes through all hooks and calls OnBeforeHandleMessage, then handles the message,
+            // then goes thorugh all hooks and calls OnAfterHandleMessage.
+            // This ensures each message only manages to activate a single message hook - because we know that only
+            // one message will ever be handled between OnBeforeHandleMessage and OnAfterHandleMessage,
+            // we can reset the flag here, and then in OnAfterHandleMessage, the moment the message matches a hook,
+            // it'll flip this flag back on, and then other hooks will stop checking that message.
+            // Without this flag, waiting for 10 messages of the same type isn't possible - all 10 hooks would get
+            // tripped by the first message.
+            CurrentMessageHasTriggerdAHook = false;
         }
 
         public void OnAfterReceiveMessage(ulong senderId, Type messageType, int messageSizeBytes)
         {
+            if (!CurrentMessageHasTriggerdAHook && IsWaiting && (HandleCheck == null || HandleCheck.Invoke(messageType)))
+            {
+                IsWaiting = false;
+                CurrentMessageHasTriggerdAHook = true;
+            }
         }
 
         public void OnBeforeSendBatch(ulong clientId, int messageCount, int batchSizeInBytes, NetworkDelivery delivery)
@@ -57,13 +79,23 @@ namespace Unity.Netcode.TestHelpers.Runtime
 
         public void OnBeforeHandleMessage<T>(ref T message, ref NetworkContext context) where T : INetworkMessage
         {
+            // The way the system works, it goes through all hooks and calls OnBeforeHandleMessage, then handles the message,
+            // then goes thorugh all hooks and calls OnAfterHandleMessage.
+            // This ensures each message only manages to activate a single message hook - because we know that only
+            // one message will ever be handled between OnBeforeHandleMessage and OnAfterHandleMessage,
+            // we can reset the flag here, and then in OnAfterHandleMessage, the moment the message matches a hook,
+            // it'll flip this flag back on, and then other hooks will stop checking that message.
+            // Without this flag, waiting for 10 messages of the same type isn't possible - all 10 hooks would get
+            // tripped by the first message.
+            CurrentMessageHasTriggerdAHook = false;
         }
 
         public void OnAfterHandleMessage<T>(ref T message, ref NetworkContext context) where T : INetworkMessage
         {
-            if (IsWaiting && (ReceiptCheck == null || ReceiptCheck.Invoke(message)))
+            if (!CurrentMessageHasTriggerdAHook && IsWaiting && (HandleCheck == null || HandleCheck.Invoke(message)))
             {
                 IsWaiting = false;
+                CurrentMessageHasTriggerdAHook = true;
             }
         }
     }

TestHelpers/Runtime/MessageHooksConditional.cs

@@ -1,3 +1,4 @@
+using System;
 using System.Collections.Generic;
 using System.Linq;
 using NUnit.Framework;
@@ -63,18 +64,34 @@ namespace Unity.Netcode.TestHelpers.Runtime
         }
     }
 
+    public enum ReceiptType
+    {
+        Received,
+        Handled
+    }
+
     public class MessageHookEntry
     {
         internal MessageHooks MessageHooks;
         protected NetworkManager m_NetworkManager;
         private MessageHooks.MessageReceiptCheck m_MessageReceiptCheck;
+        private MessageHooks.MessageHandleCheck m_MessageHandleCheck;
         internal string MessageType;
+        private ReceiptType m_ReceiptType;
 
         public void Initialize()
         {
-            Assert.IsNotNull(m_MessageReceiptCheck, $"{nameof(m_MessageReceiptCheck)} is null, did you forget to initialize?");
             MessageHooks = new MessageHooks();
-            MessageHooks.ReceiptCheck = m_MessageReceiptCheck;
+            if (m_ReceiptType == ReceiptType.Handled)
+            {
+                Assert.IsNotNull(m_MessageHandleCheck, $"{nameof(m_MessageHandleCheck)} is null, did you forget to initialize?");
+                MessageHooks.HandleCheck = m_MessageHandleCheck;
+            }
+            else
+            {
+                Assert.IsNotNull(m_MessageReceiptCheck, $"{nameof(m_MessageReceiptCheck)} is null, did you forget to initialize?");
+                MessageHooks.ReceiptCheck = m_MessageReceiptCheck;
+            }
             Assert.IsNotNull(m_NetworkManager.MessagingSystem, $"{nameof(NetworkManager.MessagingSystem)} is null! Did you forget to start first?");
             m_NetworkManager.MessagingSystem.Hook(MessageHooks);
         }
@@ -82,14 +99,41 @@ namespace Unity.Netcode.TestHelpers.Runtime
         internal void AssignMessageType<T>() where T : INetworkMessage
         {
             MessageType = typeof(T).Name;
-            m_MessageReceiptCheck = MessageHooks.CheckForMessageOfType<T>;
+            if (m_ReceiptType == ReceiptType.Handled)
+            {
+                m_MessageHandleCheck = MessageHooks.CheckForMessageOfTypeHandled<T>;
+            }
+            else
+            {
+                m_MessageReceiptCheck = MessageHooks.CheckForMessageOfTypeReceived<T>;
+            }
             Initialize();
         }
 
-        public MessageHookEntry(NetworkManager networkManager)
+        internal void AssignMessageType(Type type)
+        {
+            MessageType = type.Name;
+            if (m_ReceiptType == ReceiptType.Handled)
+            {
+                m_MessageHandleCheck = (message) =>
+                {
+                    return message.GetType() == type;
+                };
+            }
+            else
+            {
+                m_MessageReceiptCheck = (messageType) =>
+                {
+                    return messageType == type;
+                };
+            }
+            Initialize();
+        }
+
+        public MessageHookEntry(NetworkManager networkManager, ReceiptType type = ReceiptType.Handled)
         {
             m_NetworkManager = networkManager;
+            m_ReceiptType = type;
         }
     }
 }
-

TestHelpers/Runtime/Metrics/RpcTestComponent.cs

@@ -14,7 +14,7 @@ namespace Unity.Netcode.TestHelpers.Runtime.Metrics
         }
 
         [ClientRpc]
-        public void MyClientRpc()
+        public void MyClientRpc(ClientRpcParams rpcParams = default)
         {
             OnClientRpcAction?.Invoke();
         }

TestHelpers/Runtime/Metrics/WaitForEventMetricValues.cs

@@ -1,10 +1,6 @@
 #if MULTIPLAYER_TOOLS
-using System;
-using System.Collections;
 using System.Collections.Generic;
-using System.Diagnostics;
 using System.Linq;
-using NUnit.Framework;
 using Unity.Multiplayer.Tools.MetricTypes;
 using Unity.Multiplayer.Tools.NetStats;
 
@@ -12,10 +8,11 @@ namespace Unity.Netcode.TestHelpers.Runtime.Metrics
 {
     internal class WaitForEventMetricValues<TMetric> : WaitForMetricValues<TMetric>
     {
-        IReadOnlyCollection<TMetric> m_EventValues;
+        private IReadOnlyCollection<TMetric> m_EventValues;
 
         public delegate bool EventFilter(TMetric metric);
-        EventFilter m_EventFilterDelegate;
+
+        private EventFilter m_EventFilterDelegate;
 
         public WaitForEventMetricValues(IMetricDispatcher dispatcher, DirectionalMetricInfo directionalMetricName)
             : base(dispatcher, directionalMetricName)

TestHelpers/Runtime/NetcodeIntegrationTest.cs

@@ -7,7 +7,7 @@ using UnityEngine;
 using UnityEngine.SceneManagement;
 using UnityEngine.TestTools;
 using System.Runtime.CompilerServices;
-
+using Unity.Netcode.RuntimeTests;
 using Object = UnityEngine.Object;
 
 namespace Unity.Netcode.TestHelpers.Runtime
@@ -23,7 +23,9 @@ namespace Unity.Netcode.TestHelpers.Runtime
         /// </summary>
         internal static bool IsRunning { get; private set; }
         protected static TimeoutHelper s_GlobalTimeoutHelper = new TimeoutHelper(8.0f);
-        protected static WaitForSeconds s_DefaultWaitForTick = new WaitForSeconds(1.0f / k_DefaultTickRate);
+        protected static WaitForSecondsRealtime s_DefaultWaitForTick = new WaitForSecondsRealtime(1.0f / k_DefaultTickRate);
+
+        public NetcodeLogAssert NetcodeLogAssert;
 
         /// <summary>
         /// Registered list of all NetworkObjects spawned.
@@ -129,6 +131,18 @@ namespace Unity.Netcode.TestHelpers.Runtime
 
         protected bool m_EnableVerboseDebug { get; set; }
 
+        /// <summary>
+        /// When set to true, this will bypass the entire
+        /// wait for clients to connect process.
+        /// </summary>
+        /// <remarks>
+        /// CAUTION:
+        /// Setting this to true will bypass other helper
+        /// identification related code, so this should only
+        /// be used for connection failure oriented testing
+        /// </remarks>
+        protected bool m_BypassConnectionTimeout { get; set; }
+
         /// <summary>
         /// Used to display the various integration test
         /// stages and can be used to log verbose information
@@ -207,6 +221,7 @@ namespace Unity.Netcode.TestHelpers.Runtime
         {
             VerboseDebug($"Entering {nameof(SetUp)}");
 
+            NetcodeLogAssert = new NetcodeLogAssert();
             yield return OnSetup();
             if (m_NetworkManagerInstatiationMode == NetworkManagerInstatiationMode.AllTests && m_ServerNetworkManager == null ||
                 m_NetworkManagerInstatiationMode == NetworkManagerInstatiationMode.PerTest)
@@ -336,7 +351,7 @@ namespace Unity.Netcode.TestHelpers.Runtime
 
             if (m_ServerNetworkManager != null)
             {
-                s_DefaultWaitForTick = new WaitForSeconds(1.0f / m_ServerNetworkManager.NetworkConfig.TickRate);
+                s_DefaultWaitForTick = new WaitForSecondsRealtime(1.0f / m_ServerNetworkManager.NetworkConfig.TickRate);
             }
 
             // Set the player prefab for the server and clients
@@ -452,31 +467,36 @@ namespace Unity.Netcode.TestHelpers.Runtime
                 // Notification that the server and clients have been started
                 yield return OnStartedServerAndClients();
 
-                // Wait for all clients to connect
-                yield return WaitForClientsConnectedOrTimeOut();
-                AssertOnTimeout($"{nameof(StartServerAndClients)} timed out waiting for all clients to be connected!");
-
-                if (m_UseHost || m_ServerNetworkManager.IsHost)
+                // When true, we skip everything else (most likely a connection oriented test)
+                if (!m_BypassConnectionTimeout)
                 {
-                    // Add the server player instance to all m_ClientSidePlayerNetworkObjects entries
-                    var serverPlayerClones = Object.FindObjectsOfType<NetworkObject>().Where((c) => c.IsPlayerObject && c.OwnerClientId == m_ServerNetworkManager.LocalClientId);
-                    foreach (var playerNetworkObject in serverPlayerClones)
+                    // Wait for all clients to connect
+                    yield return WaitForClientsConnectedOrTimeOut();
+
+                    AssertOnTimeout($"{nameof(StartServerAndClients)} timed out waiting for all clients to be connected!");
+
+                    if (m_UseHost || m_ServerNetworkManager.IsHost)
                     {
-                        if (!m_PlayerNetworkObjects.ContainsKey(playerNetworkObject.NetworkManager.LocalClientId))
+                        // Add the server player instance to all m_ClientSidePlayerNetworkObjects entries
+                        var serverPlayerClones = Object.FindObjectsOfType<NetworkObject>().Where((c) => c.IsPlayerObject && c.OwnerClientId == m_ServerNetworkManager.LocalClientId);
+                        foreach (var playerNetworkObject in serverPlayerClones)
                         {
-                            m_PlayerNetworkObjects.Add(playerNetworkObject.NetworkManager.LocalClientId, new Dictionary<ulong, NetworkObject>());
+                            if (!m_PlayerNetworkObjects.ContainsKey(playerNetworkObject.NetworkManager.LocalClientId))
+                            {
+                                m_PlayerNetworkObjects.Add(playerNetworkObject.NetworkManager.LocalClientId, new Dictionary<ulong, NetworkObject>());
+                            }
+                            m_PlayerNetworkObjects[playerNetworkObject.NetworkManager.LocalClientId].Add(m_ServerNetworkManager.LocalClientId, playerNetworkObject);
                         }
-                        m_PlayerNetworkObjects[playerNetworkObject.NetworkManager.LocalClientId].Add(m_ServerNetworkManager.LocalClientId, playerNetworkObject);
                     }
+
+                    ClientNetworkManagerPostStartInit();
+
+                    // Notification that at this time the server and client(s) are instantiated,
+                    // started, and connected on both sides.
+                    yield return OnServerAndClientsConnected();
+
+                    VerboseDebug($"Exiting {nameof(StartServerAndClients)}");
                 }
-
-                ClientNetworkManagerPostStartInit();
-
-                // Notification that at this time the server and client(s) are instantiated,
-                // started, and connected on both sides.
-                yield return OnServerAndClientsConnected();
-
-                VerboseDebug($"Exiting {nameof(StartServerAndClients)}");
             }
         }
 
@@ -571,7 +591,7 @@ namespace Unity.Netcode.TestHelpers.Runtime
             UnloadRemainingScenes();
 
             // reset the m_ServerWaitForTick for the next test to initialize
-            s_DefaultWaitForTick = new WaitForSeconds(1.0f / k_DefaultTickRate);
+            s_DefaultWaitForTick = new WaitForSecondsRealtime(1.0f / k_DefaultTickRate);
             VerboseDebug($"Exiting {nameof(ShutdownAndCleanUp)}");
         }
 
@@ -596,6 +616,7 @@ namespace Unity.Netcode.TestHelpers.Runtime
             }
 
             VerboseDebug($"Exiting {nameof(TearDown)}");
+            NetcodeLogAssert.Dispose();
         }
 
         /// <summary>
@@ -758,6 +779,41 @@ namespace Unity.Netcode.TestHelpers.Runtime
             yield return WaitForClientsConnectedOrTimeOut(m_ClientNetworkManagers);
         }
 
+        internal IEnumerator WaitForMessageReceived<T>(List<NetworkManager> wiatForReceivedBy, ReceiptType type = ReceiptType.Handled) where T : INetworkMessage
+        {
+            // Build our message hook entries tables so we can determine if all clients received spawn or ownership messages
+            var messageHookEntriesForSpawn = new List<MessageHookEntry>();
+            foreach (var clientNetworkManager in wiatForReceivedBy)
+            {
+                var messageHook = new MessageHookEntry(clientNetworkManager, type);
+                messageHook.AssignMessageType<T>();
+                messageHookEntriesForSpawn.Add(messageHook);
+            }
+            // Used to determine if all clients received the CreateObjectMessage
+            var hooks = new MessageHooksConditional(messageHookEntriesForSpawn);
+            yield return WaitForConditionOrTimeOut(hooks);
+            Assert.False(s_GlobalTimeoutHelper.TimedOut);
+        }
+
+        internal IEnumerator WaitForMessagesReceived(List<Type> messagesInOrder, List<NetworkManager> wiatForReceivedBy, ReceiptType type = ReceiptType.Handled)
+        {
+            // Build our message hook entries tables so we can determine if all clients received spawn or ownership messages
+            var messageHookEntriesForSpawn = new List<MessageHookEntry>();
+            foreach (var clientNetworkManager in wiatForReceivedBy)
+            {
+                foreach (var message in messagesInOrder)
+                {
+                    var messageHook = new MessageHookEntry(clientNetworkManager, type);
+                    messageHook.AssignMessageType(message);
+                    messageHookEntriesForSpawn.Add(messageHook);
+                }
+            }
+            // Used to determine if all clients received the CreateObjectMessage
+            var hooks = new MessageHooksConditional(messageHookEntriesForSpawn);
+            yield return WaitForConditionOrTimeOut(hooks);
+            Assert.False(s_GlobalTimeoutHelper.TimedOut);
+        }
+
         /// <summary>
         /// Creates a basic NetworkObject test prefab, assigns it to a new
         /// NetworkPrefab entry, and then adds it to the server and client(s)
@@ -869,12 +925,14 @@ namespace Unity.Netcode.TestHelpers.Runtime
         /// Constructor that allows you To break tests up as a host
         /// and a server.
         /// Example: Decorate your child derived class with TestFixture
-        /// and then create a constructor at the child level
+        /// and then create a constructor at the child level.
+        /// Don't forget to set your constructor public, else Unity will
+        /// give you a hard to decipher error
         /// [TestFixture(HostOrServer.Host)]
         /// [TestFixture(HostOrServer.Server)]
         /// public class MyChildClass : NetcodeIntegrationTest
         /// {
-        ///     MyChildClass(HostOrServer hostOrServer) : base(hostOrServer) { }
+        ///     public MyChildClass(HostOrServer hostOrServer) : base(hostOrServer) { }
         /// }
         /// </summary>
         /// <param name="hostOrServer"></param>

TestHelpers/Runtime/NetcodeLogAssert.cs

@@ -0,0 +1,152 @@
+using System;
+using System.Collections.Generic;
+using System.Text.RegularExpressions;
+using NUnit.Framework;
+using UnityEngine;
+
+namespace Unity.Netcode.RuntimeTests
+{
+    public class NetcodeLogAssert
+    {
+        private struct LogData
+        {
+            public LogType LogType;
+            public string Message;
+            public string StackTrace;
+        }
+
+        private readonly object m_Lock = new object();
+        private bool m_Disposed;
+
+        private List<LogData> AllLogs { get; }
+
+        public NetcodeLogAssert()
+        {
+            AllLogs = new List<LogData>();
+            Activate();
+        }
+
+        private void Activate()
+        {
+            Application.logMessageReceivedThreaded += AddLog;
+        }
+
+        private void Deactivate()
+        {
+            Application.logMessageReceivedThreaded -= AddLog;
+        }
+
+        public void AddLog(string message, string stacktrace, LogType type)
+        {
+            lock (m_Lock)
+            {
+                var log = new LogData
+                {
+                    LogType = type,
+                    Message = message,
+                    StackTrace = stacktrace,
+                };
+
+                AllLogs.Add(log);
+            }
+        }
+
+        public void Dispose()
+        {
+            Dispose(true);
+            GC.SuppressFinalize(this);
+        }
+
+        private void Dispose(bool disposing)
+        {
+            if (m_Disposed)
+            {
+                return;
+            }
+
+            m_Disposed = true;
+
+            if (disposing)
+            {
+                Deactivate();
+            }
+        }
+
+        public void LogWasNotReceived(LogType type, string message)
+        {
+            lock (m_Lock)
+            {
+                foreach (var logEvent in AllLogs)
+                {
+                    if (logEvent.LogType == type && message.Equals(logEvent.Message))
+                    {
+                        Assert.Fail($"Unexpected log: [{logEvent.LogType}] {logEvent.Message}");
+                    }
+                }
+            }
+        }
+
+        public void LogWasNotReceived(LogType type, Regex messageRegex)
+        {
+            lock (m_Lock)
+            {
+                foreach (var logEvent in AllLogs)
+                {
+                    if (logEvent.LogType == type && messageRegex.IsMatch(logEvent.Message))
+                    {
+                        Assert.Fail($"Unexpected log: [{logEvent.LogType}] {logEvent.Message}");
+                    }
+                }
+            }
+        }
+
+        public void LogWasReceived(LogType type, string message)
+        {
+            lock (m_Lock)
+            {
+                var found = false;
+                foreach (var logEvent in AllLogs)
+                {
+                    if (logEvent.LogType == type && message.Equals(logEvent.Message))
+                    {
+                        found = true;
+                        break;
+                    }
+                }
+
+                if (!found)
+                {
+                    Assert.Fail($"Expected log was not received: [{type}] {message}");
+                }
+            }
+        }
+
+        public void LogWasReceived(LogType type, Regex messageRegex)
+        {
+            lock (m_Lock)
+            {
+                var found = false;
+                foreach (var logEvent in AllLogs)
+                {
+                    if (logEvent.LogType == type && messageRegex.IsMatch(logEvent.Message))
+                    {
+                        found = true;
+                    }
+                }
+
+                if (!found)
+                {
+                    Assert.Fail($"Expected log was not received: [{type}] {messageRegex}");
+                }
+            }
+        }
+
+        public void Reset()
+        {
+            lock (m_Lock)
+            {
+                AllLogs.Clear();
+            }
+        }
+    }
+}

TestHelpers/Runtime/NetcodeLogAssert.cs.meta

@@ -0,0 +1,3 @@
+fileFormatVersion: 2
+guid: 61774c54cd14423ca4de6d56c9fd0fe8
+timeCreated: 1661800793

TestHelpers/Runtime/NetworkVariableHelper.cs

@@ -13,7 +13,7 @@ namespace Unity.Netcode.TestHelpers.Runtime
     /// From both we can then at least determine if the value indeed changed
     /// </summary>
     /// <typeparam name="T"></typeparam>
-    public class NetworkVariableHelper<T> : NetworkVariableBaseHelper where T : unmanaged
+    public class NetworkVariableHelper<T> : NetworkVariableBaseHelper
     {
         private readonly NetworkVariable<T> m_NetworkVariable;
         public delegate void OnMyValueChangedDelegateHandler(T previous, T next);
@@ -50,7 +50,7 @@ namespace Unity.Netcode.TestHelpers.Runtime
         {
             if (previous is ValueType testValueType)
             {
-                CheckVariableChanged(previous, next);
+                CheckVariableChanged(previous as ValueType, next as ValueType);
             }
             else
             {

TestHelpers/Runtime/com.unity.netcode.testhelpers.runtime.asmdef

@@ -11,6 +11,9 @@
     "optionalUnityReferences": [
         "TestAssemblies"
     ],
+    "defineConstraints": [
+        "UNITY_INCLUDE_TESTS"
+    ],
     "versionDefines": [
         {
             "name": "com.unity.multiplayer.tools",

Tests/Editor/Build/BuildTests.cs

@@ -4,7 +4,6 @@ using NUnit.Framework;
 using UnityEditor;
 using UnityEditor.Build.Reporting;
 using UnityEngine;
-using UnityEngine.TestTools;
 
 namespace Unity.Netcode.EditorTests
 {
@@ -21,20 +20,20 @@ namespace Unity.Netcode.EditorTests
             var buildTargetGroup = BuildPipeline.GetBuildTargetGroup(buildTarget);
             var buildTargetSupported = BuildPipeline.IsBuildTargetSupported(buildTargetGroup, buildTarget);
 
-            var buildReport = BuildPipeline.BuildPlayer(
-                new[] { Path.Combine(packagePath, DefaultBuildScenePath) },
-                Path.Combine(Path.GetDirectoryName(Application.dataPath), "Builds", nameof(BuildTests)),
-                buildTarget,
-                BuildOptions.None
-            );
-
             if (buildTargetSupported)
             {
+                var buildReport = BuildPipeline.BuildPlayer(
+                    new[] { Path.Combine(packagePath, DefaultBuildScenePath) },
+                    Path.Combine(Path.GetDirectoryName(Application.dataPath), "Builds", nameof(BuildTests)),
+                    buildTarget,
+                    BuildOptions.None
+                );
+
                 Assert.AreEqual(BuildResult.Succeeded, buildReport.summary.result);
             }
             else
             {
-                LogAssert.Expect(LogType.Error, "Error building player because build target was unsupported");
+                Debug.Log($"Skipped building player due to Unsupported Build Target");
             }
         }
     }

Tests/Editor/InterpolatorTests.cs

@@ -105,6 +105,7 @@ namespace Unity.Netcode.EditorTests
             Assert.That(interpolator.GetInterpolatedValue(), Is.EqualTo(2f).Within(k_Precision));
         }
 
+        [Ignore("TODO: Fix this test to still handle testing message loss without extrapolation")]
         [Test]
         public void MessageLoss()
         {
@@ -305,6 +306,7 @@ namespace Unity.Netcode.EditorTests
             Assert.Throws<InvalidOperationException>(() => interpolator.Update(1f, serverTime));
         }
 
+        [Ignore("TODO: Fix this test to still test duplicated values without extrapolation")]
         [Test]
         public void TestDuplicatedValues()
         {

Tests/Editor/Messaging/MessageRegistrationTests.cs

@@ -1,3 +1,4 @@
+using System;
 using System.Collections.Generic;
 using NUnit.Framework;
 
@@ -136,9 +137,9 @@ namespace Unity.Netcode.EditorTests
         {
             var sender = new NopMessageSender();
 
-            var systemOne = new MessagingSystem(sender, null, new TestMessageProviderOne());
-            var systemTwo = new MessagingSystem(sender, null, new TestMessageProviderTwo());
-            var systemThree = new MessagingSystem(sender, null, new TestMessageProviderThree());
+            using var systemOne = new MessagingSystem(sender, null, new TestMessageProviderOne());
+            using var systemTwo = new MessagingSystem(sender, null, new TestMessageProviderTwo());
+            using var systemThree = new MessagingSystem(sender, null, new TestMessageProviderThree());
 
             using (systemOne)
             using (systemTwo)
@@ -160,9 +161,9 @@ namespace Unity.Netcode.EditorTests
         {
             var sender = new NopMessageSender();
 
-            var systemOne = new MessagingSystem(sender, null, new TestMessageProviderOne());
-            var systemTwo = new MessagingSystem(sender, null, new TestMessageProviderTwo());
-            var systemThree = new MessagingSystem(sender, null, new TestMessageProviderThree());
+            using var systemOne = new MessagingSystem(sender, null, new TestMessageProviderOne());
+            using var systemTwo = new MessagingSystem(sender, null, new TestMessageProviderTwo());
+            using var systemThree = new MessagingSystem(sender, null, new TestMessageProviderThree());
 
             using (systemOne)
             using (systemTwo)
@@ -179,5 +180,122 @@ namespace Unity.Netcode.EditorTests
                 Assert.AreEqual(handlerFour, systemThree.MessageHandlers[systemThree.GetMessageType(typeof(TestMessageFour))]);
             }
         }
+
+        internal class AAAEarlyLexicographicNetworkMessage : INetworkMessage
+        {
+            public void Serialize(FastBufferWriter writer)
+            {
+            }
+
+            public bool Deserialize(FastBufferReader reader, ref NetworkContext context)
+            {
+                return true;
+            }
+
+            public void Handle(ref NetworkContext context)
+            {
+            }
+        }
+
+#pragma warning disable IDE1006
+        internal class zzzLateLexicographicNetworkMessage : AAAEarlyLexicographicNetworkMessage
+        {
+        }
+#pragma warning restore IDE1006
+
+        internal class OrderingMessageProvider : IMessageProvider
+        {
+            public List<MessagingSystem.MessageWithHandler> GetMessages()
+            {
+                var listMessages = new List<MessagingSystem.MessageWithHandler>();
+
+                var messageWithHandler = new MessagingSystem.MessageWithHandler();
+
+                messageWithHandler.MessageType = typeof(zzzLateLexicographicNetworkMessage);
+                listMessages.Add(messageWithHandler);
+
+                messageWithHandler.MessageType = typeof(ConnectionRequestMessage);
+                listMessages.Add(messageWithHandler);
+
+                messageWithHandler.MessageType = typeof(ConnectionApprovedMessage);
+                listMessages.Add(messageWithHandler);
+
+                messageWithHandler.MessageType = typeof(OrderingMessage);
+                listMessages.Add(messageWithHandler);
+
+                messageWithHandler.MessageType = typeof(AAAEarlyLexicographicNetworkMessage);
+                listMessages.Add(messageWithHandler);
+
+                return listMessages;
+            }
+        }
+
+        [Test]
+        public void MessagesGetPrioritizedCorrectly()
+        {
+            var sender = new NopMessageSender();
+            var provider = new OrderingMessageProvider();
+            using var messagingSystem = new MessagingSystem(sender, null, provider);
+
+            // the 3 priority messages should appear first, in lexicographic order
+            Assert.AreEqual(messagingSystem.MessageTypes[0], typeof(ConnectionApprovedMessage));
+            Assert.AreEqual(messagingSystem.MessageTypes[1], typeof(ConnectionRequestMessage));
+            Assert.AreEqual(messagingSystem.MessageTypes[2], typeof(OrderingMessage));
+
+            // the other should follow after
+            Assert.AreEqual(messagingSystem.MessageTypes[3], typeof(AAAEarlyLexicographicNetworkMessage));
+            Assert.AreEqual(messagingSystem.MessageTypes[4], typeof(zzzLateLexicographicNetworkMessage));
+
+            // there should not be any extras
+            Assert.AreEqual(messagingSystem.MessageHandlerCount, 5);
+
+            // reorder the zzz one to position 3
+            messagingSystem.ReorderMessage(3, XXHash.Hash32(typeof(zzzLateLexicographicNetworkMessage).FullName));
+
+            // the 3 priority messages should still appear first, in lexicographic order
+            Assert.AreEqual(messagingSystem.MessageTypes[0], typeof(ConnectionApprovedMessage));
+            Assert.AreEqual(messagingSystem.MessageTypes[1], typeof(ConnectionRequestMessage));
+            Assert.AreEqual(messagingSystem.MessageTypes[2], typeof(OrderingMessage));
+
+            // the other should follow after, but reordered
+            Assert.AreEqual(messagingSystem.MessageTypes[3], typeof(zzzLateLexicographicNetworkMessage));
+            Assert.AreEqual(messagingSystem.MessageTypes[4], typeof(AAAEarlyLexicographicNetworkMessage));
+
+            // there should still not be any extras
+            Assert.AreEqual(messagingSystem.MessageHandlerCount, 5);
+
+            // verify we get an exception when asking for an invalid position
+            try
+            {
+                messagingSystem.ReorderMessage(-1, XXHash.Hash32(typeof(zzzLateLexicographicNetworkMessage).FullName));
+                Assert.Fail();
+            }
+            catch (ArgumentException)
+            {
+            }
+
+            // reorder the zzz one to position 3, again, to check nothing bad happens
+            messagingSystem.ReorderMessage(3, XXHash.Hash32(typeof(zzzLateLexicographicNetworkMessage).FullName));
+
+            // the two non-priority should not have moved
+            Assert.AreEqual(messagingSystem.MessageTypes[3], typeof(zzzLateLexicographicNetworkMessage));
+            Assert.AreEqual(messagingSystem.MessageTypes[4], typeof(AAAEarlyLexicographicNetworkMessage));
+
+            // there should still not be any extras
+            Assert.AreEqual(messagingSystem.MessageHandlerCount, 5);
+
+            // 4242 is a random hash that should not match anything
+            messagingSystem.ReorderMessage(3, 4242);
+
+            // that should result in an extra entry
+            Assert.AreEqual(messagingSystem.MessageHandlerCount, 6);
+
+            // with a null handler
+            Assert.AreEqual(messagingSystem.MessageHandlers[3], null);
+
+            // and it should have bumped the previous messages down
+            Assert.AreEqual(messagingSystem.MessageTypes[4], typeof(zzzLateLexicographicNetworkMessage));
+            Assert.AreEqual(messagingSystem.MessageTypes[5], typeof(AAAEarlyLexicographicNetworkMessage));
+        }
     }
 }

Tests/Editor/Messaging/MessageSendingTests.cs

@@ -1,8 +1,12 @@
 using System;
 using System.Collections.Generic;
+using System.Text.RegularExpressions;
 using NUnit.Framework;
 using Unity.Collections;
 using Unity.Collections.LowLevel.Unsafe;
+using UnityEngine;
+using UnityEngine.TestTools;
+using Random = System.Random;
 
 namespace Unity.Netcode.EditorTests
 {
@@ -40,11 +44,24 @@ namespace Unity.Netcode.EditorTests
             }
         }
 
-        private class TestMessageProvider : IMessageProvider
+        private class TestMessageProvider : IMessageProvider, IDisposable
         {
+            // Keep track of what we sent
+            private List<List<MessagingSystem.MessageWithHandler>> m_CachedMessages = new List<List<MessagingSystem.MessageWithHandler>>();
+
+            public void Dispose()
+            {
+                foreach (var cachedItem in m_CachedMessages)
+                {
+                    // Clear out any references to MessagingSystem.MessageWithHandlers
+                    cachedItem.Clear();
+                }
+                m_CachedMessages.Clear();
+            }
+
             public List<MessagingSystem.MessageWithHandler> GetMessages()
             {
-                return new List<MessagingSystem.MessageWithHandler>
+                var messageList = new List<MessagingSystem.MessageWithHandler>
                 {
                     new MessagingSystem.MessageWithHandler
                     {
@@ -52,9 +69,13 @@ namespace Unity.Netcode.EditorTests
                         Handler = MessagingSystem.ReceiveMessage<TestMessage>
                     }
                 };
+                // Track messages sent
+                m_CachedMessages.Add(messageList);
+                return messageList;
             }
         }
 
+        private TestMessageProvider m_TestMessageProvider;
         private TestMessageSender m_MessageSender;
         private MessagingSystem m_MessagingSystem;
         private ulong[] m_Clients = { 0 };
@@ -63,15 +84,16 @@ namespace Unity.Netcode.EditorTests
         public void SetUp()
         {
             TestMessage.Serialized = false;
-
             m_MessageSender = new TestMessageSender();
-            m_MessagingSystem = new MessagingSystem(m_MessageSender, this, new TestMessageProvider());
+            m_TestMessageProvider = new TestMessageProvider();
+            m_MessagingSystem = new MessagingSystem(m_MessageSender, this, m_TestMessageProvider);
             m_MessagingSystem.ClientConnected(0);
         }
 
         [TearDown]
         public void TearDown()
         {
+            m_TestMessageProvider.Dispose();
             m_MessagingSystem.Dispose();
         }
 
@@ -224,5 +246,56 @@ namespace Unity.Netcode.EditorTests
                 Assert.AreEqual(message2, receivedMessage2);
             }
         }
+
+        private class TestNoHandlerMessageProvider : IMessageProvider
+        {
+            public List<MessagingSystem.MessageWithHandler> GetMessages()
+            {
+                return new List<MessagingSystem.MessageWithHandler>
+                {
+                    new MessagingSystem.MessageWithHandler
+                    {
+                        MessageType = typeof(TestMessage),
+                        Handler = null
+                    }
+                };
+            }
+        }
+
+        [Test]
+        public void WhenReceivingAMessageWithoutAHandler_ExceptionIsLogged()
+        {
+            // If a MessagingSystem already exists then dispose of it before creating a new MessagingSystem (otherwise memory leak)
+            if (m_MessagingSystem != null)
+            {
+                m_MessagingSystem.Dispose();
+                m_MessagingSystem = null;
+            }
+
+            // Since m_MessagingSystem is disposed during teardown we don't need to worry about that here.
+            m_MessagingSystem = new MessagingSystem(new NopMessageSender(), this, new TestNoHandlerMessageProvider());
+            m_MessagingSystem.ClientConnected(0);
+
+            var messageHeader = new MessageHeader
+            {
+                MessageSize = (ushort)UnsafeUtility.SizeOf<TestMessage>(),
+                MessageType = m_MessagingSystem.GetMessageType(typeof(TestMessage)),
+            };
+            var message = GetMessage();
+
+            var writer = new FastBufferWriter(1300, Allocator.Temp);
+            using (writer)
+            {
+                writer.TryBeginWrite(FastBufferWriter.GetWriteSize(message));
+                writer.WriteValue(message);
+
+                var reader = new FastBufferReader(writer, Allocator.Temp);
+                using (reader)
+                {
+                    m_MessagingSystem.HandleMessage(messageHeader, reader, 0, 0, 0);
+                    LogAssert.Expect(LogType.Exception, new Regex(".*HandlerNotRegisteredException.*"));
+                }
+            }
+        }
     }
 }

Tests/Editor/Metrics/NetworkMetricsRegistrationTests.cs

@@ -10,12 +10,13 @@ namespace Unity.Netcode.EditorTests.Metrics
 {
     public class NetworkMetricsRegistrationTests
     {
-        static Type[] s_MetricTypes = AppDomain.CurrentDomain.GetAssemblies()
+        private static Type[] s_MetricTypes = AppDomain.CurrentDomain.GetAssemblies()
             .SelectMany(x => x.GetTypes())
             .Where(x => x.GetInterfaces().Contains(typeof(INetworkMetricEvent)))
             .ToArray();
 
-        [TestCaseSource(nameof(s_MetricTypes))][Ignore("Disable test while we reevaluate the assumption that INetworkMetricEvent interfaces must be reported from MLAPI.")]
+        [TestCaseSource(nameof(s_MetricTypes))]
+        [Ignore("Disable test while we reevaluate the assumption that INetworkMetricEvent interfaces must be reported from MLAPI.")]
         public void ValidateThatAllMetricTypesAreRegistered(Type metricType)
         {
             var dispatcher = new NetworkMetrics().Dispatcher as MetricDispatcher;

Tests/Editor/NetworkVar/NetworkVarTests.cs

@@ -1,41 +1,55 @@
 using NUnit.Framework;
+using UnityEngine;
 
 namespace Unity.Netcode.EditorTests.NetworkVar
 {
     public class NetworkVarTests
     {
+        public class NetworkVarComponent : NetworkBehaviour
+        {
+            public NetworkVariable<int> NetworkVariable = new NetworkVariable<int>();
+        }
         [Test]
         public void TestAssignmentUnchanged()
         {
-            var intVar = new NetworkVariable<int>();
-
-            intVar.Value = 314159265;
-
-            intVar.OnValueChanged += (value, newValue) =>
+            var gameObjectMan = new GameObject();
+            var networkManager = gameObjectMan.AddComponent<NetworkManager>();
+            networkManager.BehaviourUpdater = new NetworkBehaviourUpdater();
+            var gameObject = new GameObject();
+            var networkObject = gameObject.AddComponent<NetworkObject>();
+            networkObject.NetworkManagerOwner = networkManager;
+            var networkVarComponent = gameObject.AddComponent<NetworkVarComponent>();
+            networkVarComponent.NetworkVariable.Initialize(networkVarComponent);
+            networkVarComponent.NetworkVariable.Value = 314159265;
+            networkVarComponent.NetworkVariable.OnValueChanged += (value, newValue) =>
             {
                 Assert.Fail("OnValueChanged was invoked when setting the same value");
             };
-
-            intVar.Value = 314159265;
+            networkVarComponent.NetworkVariable.Value = 314159265;
+            Object.DestroyImmediate(gameObject);
+            Object.DestroyImmediate(gameObjectMan);
         }
-
         [Test]
         public void TestAssignmentChanged()
         {
-            var intVar = new NetworkVariable<int>();
-
-            intVar.Value = 314159265;
-
+            var gameObjectMan = new GameObject();
+            var networkManager = gameObjectMan.AddComponent<NetworkManager>();
+            networkManager.BehaviourUpdater = new NetworkBehaviourUpdater();
+            var gameObject = new GameObject();
+            var networkObject = gameObject.AddComponent<NetworkObject>();
+            var networkVarComponent = gameObject.AddComponent<NetworkVarComponent>();
+            networkObject.NetworkManagerOwner = networkManager;
+            networkVarComponent.NetworkVariable.Initialize(networkVarComponent);
+            networkVarComponent.NetworkVariable.Value = 314159265;
             var changed = false;
-
-            intVar.OnValueChanged += (value, newValue) =>
+            networkVarComponent.NetworkVariable.OnValueChanged += (value, newValue) =>
             {
                 changed = true;
             };
-
-            intVar.Value = 314159266;
-
+            networkVarComponent.NetworkVariable.Value = 314159266;
             Assert.True(changed);
+            Object.DestroyImmediate(gameObject);
+            Object.DestroyImmediate(gameObjectMan);
         }
     }
 }

Tests/Editor/Serialization/UserBitReaderAndBitWriterTests_NCCBUG175.cs

@@ -0,0 +1,95 @@
+using NUnit.Framework;
+using Unity.Collections;
+
+namespace Unity.Netcode.EditorTests
+{
+    public class UserBitReaderAndBitWriterTests_NCCBUG175
+    {
+
+        [Test]
+        public void WhenBitwiseWritingMoreThan8Bits_ValuesAreCorrect()
+        {
+            using var writer = new FastBufferWriter(1024, Allocator.Temp);
+            ulong inVal = 123456789;
+
+            for (int i = 0; i < 100; ++i)
+            {
+                writer.WriteValueSafe(i);
+            }
+
+            using (var bitWriter = writer.EnterBitwiseContext())
+            {
+                for (int i = 0; i < 16; ++i)
+                {
+                    Assert.IsTrue((bitWriter.TryBeginWriteBits(32)));
+                    bitWriter.WriteBits(inVal, 31);
+                    bitWriter.WriteBit(true);
+                }
+            }
+
+            using var reader = new FastBufferReader(writer, Allocator.Temp);
+
+            for (int i = 0; i < 100; ++i)
+            {
+                reader.ReadValueSafe(out int outVal);
+                Assert.AreEqual(i, outVal);
+            }
+
+            using var bitReader = reader.EnterBitwiseContext();
+            for (int i = 0; i < 16; ++i)
+            {
+                Assert.IsTrue(bitReader.TryBeginReadBits(32));
+                bitReader.ReadBits(out ulong outVal, 31);
+                bitReader.ReadBit(out bool bit);
+                Assert.AreEqual(inVal, outVal);
+                Assert.AreEqual(true, bit);
+            }
+        }
+
+        [Test]
+        public void WhenBitwiseReadingMoreThan8Bits_ValuesAreCorrect()
+        {
+            using var writer = new FastBufferWriter(1024, Allocator.Temp);
+            ulong inVal = 123456789;
+
+            for (int i = 0; i < 100; ++i)
+            {
+                writer.WriteValueSafe(i);
+            }
+
+            uint combined = (uint)inVal | (1u << 31);
+            writer.WriteValueSafe(combined);
+            writer.WriteValueSafe(combined);
+            writer.WriteValueSafe(combined);
+
+            using var reader = new FastBufferReader(writer, Allocator.Temp);
+
+            for (int i = 0; i < 100; ++i)
+            {
+                reader.ReadValueSafe(out int outVal);
+                Assert.AreEqual(i, outVal);
+            }
+
+            using (var bitReader = reader.EnterBitwiseContext())
+            {
+                Assert.IsTrue(bitReader.TryBeginReadBits(32));
+                bitReader.ReadBits(out ulong outVal, 31);
+                bitReader.ReadBit(out bool bit);
+                Assert.AreEqual(inVal, outVal);
+                Assert.AreEqual(true, bit);
+
+                Assert.IsTrue(bitReader.TryBeginReadBits(32));
+                bitReader.ReadBits(out outVal, 31);
+                bitReader.ReadBit(out bit);
+                Assert.AreEqual(inVal, outVal);
+                Assert.AreEqual(true, bit);
+
+                Assert.IsTrue(bitReader.TryBeginReadBits(32));
+                bitReader.ReadBits(out outVal, 31);
+                bitReader.ReadBit(out bit);
+                Assert.AreEqual(inVal, outVal);
+                Assert.AreEqual(true, bit);
+            }
+        }
+    }
+}

Tests/Editor/Serialization/UserBitReaderAndBitWriterTests_NCCBUG175.cs.meta

@@ -0,0 +1,3 @@
+fileFormatVersion: 2
+guid: adfa622d42824b70a39a30b6aa22c9c5
+timeCreated: 1660758428

Tests/Editor/Transports/BatchedSendQueueTests.cs

@@ -8,8 +8,9 @@ namespace Unity.Netcode.EditorTests
 {
     public class BatchedSendQueueTests
     {
-        private const int k_TestQueueCapacity = 1024;
-        private const int k_TestMessageSize = 42;
+        private const int k_TestQueueCapacity = 16 * 1024;
+        private const int k_TestMessageSize = 1020;
+        private const int k_NumMessagesToFillQueue = k_TestQueueCapacity / (k_TestMessageSize + BatchedSendQueue.PerMessageOverhead);
 
         private ArraySegment<byte> m_TestMessage;
 
@@ -52,7 +53,14 @@ namespace Unity.Netcode.EditorTests
         }
 
         [Test]
-        public void BatchedSendQueue_PushMessageReturnValue()
+        public void BatchedSendQueue_InitialCapacityLessThanMaximum()
+        {
+            using var q = new BatchedSendQueue(k_TestQueueCapacity);
+            Assert.AreEqual(q.Capacity, BatchedSendQueue.MinimumMinimumCapacity);
+        }
+
+        [Test]
+        public void BatchedSendQueue_PushMessage_ReturnValue()
         {
             // Will fit a single test message, but not two (with overhead included).
             var queueCapacity = (k_TestMessageSize * 2) + BatchedSendQueue.PerMessageOverhead;
@@ -64,7 +72,7 @@ namespace Unity.Netcode.EditorTests
         }
 
         [Test]
-        public void BatchedSendQueue_LengthIncreasedAfterPush()
+        public void BatchedSendQueue_PushMessage_IncreasesLength()
         {
             using var q = new BatchedSendQueue(k_TestQueueCapacity);
 
@@ -73,13 +81,12 @@ namespace Unity.Netcode.EditorTests
         }
 
         [Test]
-        public void BatchedSendQueue_PushedMessageGeneratesCopy()
+        public void BatchedSendQueue_PushMessage_SucceedsAfterConsume()
         {
             var messageLength = k_TestMessageSize + BatchedSendQueue.PerMessageOverhead;
             var queueCapacity = messageLength * 2;
 
             using var q = new BatchedSendQueue(queueCapacity);
-            using var data = new NativeArray<byte>(k_TestQueueCapacity, Allocator.Temp);
 
             q.PushMessage(m_TestMessage);
             q.PushMessage(m_TestMessage);
@@ -89,6 +96,60 @@ namespace Unity.Netcode.EditorTests
             Assert.AreEqual(queueCapacity, q.Length);
         }
 
+        [Test]
+        public void BatchedSendQueue_PushMessage_GrowsDataIfNeeded()
+        {
+            using var q = new BatchedSendQueue(k_TestQueueCapacity);
+            var messageLength = k_TestMessageSize + BatchedSendQueue.PerMessageOverhead;
+
+            Assert.AreEqual(q.Capacity, BatchedSendQueue.MinimumMinimumCapacity);
+
+            var numMessagesToFillMinimum = BatchedSendQueue.MinimumMinimumCapacity / messageLength;
+            for (int i = 0; i < numMessagesToFillMinimum; i++)
+            {
+                q.PushMessage(m_TestMessage);
+            }
+
+            Assert.AreEqual(q.Capacity, BatchedSendQueue.MinimumMinimumCapacity);
+
+            q.PushMessage(m_TestMessage);
+
+            Assert.AreEqual(q.Capacity, BatchedSendQueue.MinimumMinimumCapacity * 2);
+        }
+
+        [Test]
+        public void BatchedSendQueue_PushMessage_DoesNotGrowDataPastMaximum()
+        {
+            using var q = new BatchedSendQueue(k_TestQueueCapacity);
+
+            for (int i = 0; i < k_NumMessagesToFillQueue; i++)
+            {
+                Assert.IsTrue(q.PushMessage(m_TestMessage));
+            }
+
+            Assert.AreEqual(q.Capacity, k_TestQueueCapacity);
+            Assert.IsFalse(q.PushMessage(m_TestMessage));
+            Assert.AreEqual(q.Capacity, k_TestQueueCapacity);
+        }
+
+        [Test]
+        public void BatchedSendQueue_PushMessage_TrimsDataAfterGrowing()
+        {
+            using var q = new BatchedSendQueue(k_TestQueueCapacity);
+            var messageLength = k_TestMessageSize + BatchedSendQueue.PerMessageOverhead;
+
+            for (int i = 0; i < k_NumMessagesToFillQueue; i++)
+            {
+                Assert.IsTrue(q.PushMessage(m_TestMessage));
+            }
+
+            Assert.AreEqual(q.Capacity, k_TestQueueCapacity);
+            q.Consume(messageLength * (k_NumMessagesToFillQueue - 1));
+            Assert.IsTrue(q.PushMessage(m_TestMessage));
+            Assert.AreEqual(messageLength * 2, q.Length);
+            Assert.AreEqual(q.Capacity, BatchedSendQueue.MinimumMinimumCapacity * 2);
+        }
+
         [Test]
         public void BatchedSendQueue_FillWriterWithMessages_ReturnValue()
         {
@@ -227,7 +288,7 @@ namespace Unity.Netcode.EditorTests
         }
 
         [Test]
-        public void BatchedSendQueue_ConsumeLessThanLength()
+        public void BatchedSendQueue_Consume_LessThanLength()
         {
             using var q = new BatchedSendQueue(k_TestQueueCapacity);
 
@@ -240,7 +301,7 @@ namespace Unity.Netcode.EditorTests
         }
 
         [Test]
-        public void BatchedSendQueue_ConsumeExactLength()
+        public void BatchedSendQueue_Consume_ExactLength()
         {
             using var q = new BatchedSendQueue(k_TestQueueCapacity);
 
@@ -252,7 +313,7 @@ namespace Unity.Netcode.EditorTests
         }
 
         [Test]
-        public void BatchedSendQueue_ConsumeMoreThanLength()
+        public void BatchedSendQueue_Consume_MoreThanLength()
         {
             using var q = new BatchedSendQueue(k_TestQueueCapacity);
 
@@ -262,5 +323,20 @@ namespace Unity.Netcode.EditorTests
             Assert.AreEqual(0, q.Length);
             Assert.True(q.IsEmpty);
         }
+
+        [Test]
+        public void BatchedSendQueue_Consume_TrimsDataOnEmpty()
+        {
+            using var q = new BatchedSendQueue(k_TestQueueCapacity);
+
+            for (int i = 0; i < k_NumMessagesToFillQueue; i++)
+            {
+                q.PushMessage(m_TestMessage);
+            }
+
+            Assert.AreEqual(q.Capacity, k_TestQueueCapacity);
+            q.Consume(k_TestQueueCapacity);
+            Assert.AreEqual(q.Capacity, BatchedSendQueue.MinimumMinimumCapacity);
+        }
     }
 }

Tests/Editor/Transports/UnityTransportTests.cs

@@ -1,14 +1,15 @@
 using NUnit.Framework;
 using Unity.Netcode.Transports.UTP;
 using UnityEngine;
+using UnityEngine.TestTools;
 
 namespace Unity.Netcode.EditorTests
 {
     public class UnityTransportTests
     {
-        // Check that starting a server doesn't immediately result in faulted tasks.
+        // Check that starting an IPv4 server succeeds.
         [Test]
-        public void BasicInitServer()
+        public void UnityTransport_BasicInitServer_IPv4()
         {
             UnityTransport transport = new GameObject().AddComponent<UnityTransport>();
             transport.Initialize();
@@ -18,9 +19,9 @@ namespace Unity.Netcode.EditorTests
             transport.Shutdown();
         }
 
-        // Check that starting a client doesn't immediately result in faulted tasks.
+        // Check that starting an IPv4 client succeeds.
         [Test]
-        public void BasicInitClient()
+        public void UnityTransport_BasicInitClient_IPv4()
         {
             UnityTransport transport = new GameObject().AddComponent<UnityTransport>();
             transport.Initialize();
@@ -30,9 +31,35 @@ namespace Unity.Netcode.EditorTests
             transport.Shutdown();
         }
 
+        // Check that starting an IPv6 server succeeds.
+        [Test]
+        public void UnityTransport_BasicInitServer_IPv6()
+        {
+            UnityTransport transport = new GameObject().AddComponent<UnityTransport>();
+            transport.Initialize();
+            transport.SetConnectionData("::1", 7777);
+
+            Assert.True(transport.StartServer());
+
+            transport.Shutdown();
+        }
+
+        // Check that starting an IPv6 client succeeds.
+        [Test]
+        public void UnityTransport_BasicInitClient_IPv6()
+        {
+            UnityTransport transport = new GameObject().AddComponent<UnityTransport>();
+            transport.Initialize();
+            transport.SetConnectionData("::1", 7777);
+
+            Assert.True(transport.StartClient());
+
+            transport.Shutdown();
+        }
+
         // Check that we can't restart a server.
         [Test]
-        public void NoRestartServer()
+        public void UnityTransport_NoRestartServer()
         {
             UnityTransport transport = new GameObject().AddComponent<UnityTransport>();
             transport.Initialize();
@@ -45,7 +72,7 @@ namespace Unity.Netcode.EditorTests
 
         // Check that we can't restart a client.
         [Test]
-        public void NoRestartClient()
+        public void UnityTransport_NoRestartClient()
         {
             UnityTransport transport = new GameObject().AddComponent<UnityTransport>();
             transport.Initialize();
@@ -58,7 +85,7 @@ namespace Unity.Netcode.EditorTests
 
         // Check that we can't start both a server and client on the same transport.
         [Test]
-        public void NotBothServerAndClient()
+        public void UnityTransport_NotBothServerAndClient()
         {
             UnityTransport transport;
 
@@ -80,5 +107,24 @@ namespace Unity.Netcode.EditorTests
 
             transport.Shutdown();
         }
+
+        // Check that restarting after failure succeeds.
+        [Test]
+        public void UnityTransport_RestartSucceedsAfterFailure()
+        {
+            UnityTransport transport = new GameObject().AddComponent<UnityTransport>();
+            transport.Initialize();
+
+            transport.SetConnectionData("127.0.0.", 4242);
+            Assert.False(transport.StartServer());
+
+            LogAssert.Expect(LogType.Error, "Invalid network endpoint: 127.0.0.:4242.");
+            LogAssert.Expect(LogType.Error, "Server failed to bind");
+
+            transport.SetConnectionData("127.0.0.1", 4242);
+            Assert.True(transport.StartServer());
+
+            transport.Shutdown();
+        }
     }
 }

Tests/Editor/com.unity.netcode.editortests.asmdef

@@ -15,6 +15,9 @@
     "optionalUnityReferences": [
         "TestAssemblies"
     ],
+    "defineConstraints": [
+        "UNITY_INCLUDE_TESTS"
+    ],
     "includePlatforms": [
         "Editor"
     ],

Tests/Runtime/AddNetworkPrefabTests.cs

@@ -22,17 +22,18 @@ namespace Unity.Netcode.RuntimeTests
             // Host is irrelevant, messages don't get sent to the host "client"
             m_UseHost = false;
 
+            yield return null;
+        }
+
+        protected override void OnServerAndClientsCreated()
+        {
             m_Prefab = new GameObject("Object");
             var networkObject = m_Prefab.AddComponent<NetworkObject>();
             m_Prefab.AddComponent<EmptyComponent>();
 
             // Make it a prefab
             NetcodeIntegrationTestHelpers.MakeNetworkObjectTestPrefab(networkObject);
-            yield return null;
-        }
 
-        protected override void OnServerAndClientsCreated()
-        {
             m_ServerNetworkManager.NetworkConfig.SpawnTimeout = 0;
             m_ServerNetworkManager.NetworkConfig.ForceSamePrefabs = false;
             foreach (var client in m_ClientNetworkManagers)

Tests/Runtime/Components/NetworkVariableTestComponent.cs

@@ -1,8 +1,161 @@
+using System;
+using NUnit.Framework;
+using Unity.Collections;
 using UnityEngine;
 using Unity.Netcode.TestHelpers.Runtime;
 
 namespace Unity.Netcode.RuntimeTests
 {
+    public class ManagedNetworkSerializableType : INetworkSerializable, IEquatable<ManagedNetworkSerializableType>
+    {
+        public string Str = "";
+        public int[] Ints = Array.Empty<int>();
+        public int InMemoryValue;
+
+        public void NetworkSerialize<T>(BufferSerializer<T> serializer) where T : IReaderWriter
+        {
+            serializer.SerializeValue(ref Str, true);
+            var length = Ints.Length;
+            serializer.SerializeValue(ref length);
+            if (serializer.IsReader)
+            {
+                Ints = new int[length];
+            }
+
+            for (var i = 0; i < length; ++i)
+            {
+                var val = Ints[i];
+                serializer.SerializeValue(ref val);
+                Ints[i] = val;
+            }
+        }
+
+        public bool Equals(ManagedNetworkSerializableType other)
+        {
+            if (ReferenceEquals(null, other))
+            {
+                return false;
+            }
+
+            if (ReferenceEquals(this, other))
+            {
+                return true;
+            }
+
+            if (Str != other.Str)
+            {
+                return false;
+            }
+
+            if (Ints.Length != other.Ints.Length)
+            {
+                return false;
+            }
+
+            for (var i = 0; i < Ints.Length; ++i)
+            {
+                if (Ints[i] != other.Ints[i])
+                {
+                    return false;
+                }
+            }
+
+            return true;
+        }
+
+        public override bool Equals(object obj)
+        {
+            if (ReferenceEquals(null, obj))
+            {
+                return false;
+            }
+
+            if (ReferenceEquals(this, obj))
+            {
+                return true;
+            }
+
+            if (obj.GetType() != GetType())
+            {
+                return false;
+            }
+
+            return Equals((ManagedNetworkSerializableType)obj);
+        }
+
+        public override int GetHashCode()
+        {
+            return 0;
+        }
+    }
+    public struct UnmanagedNetworkSerializableType : INetworkSerializable, IEquatable<UnmanagedNetworkSerializableType>
+    {
+        public FixedString32Bytes Str;
+        public int Int;
+        public int InMemoryValue;
+
+        public void NetworkSerialize<T>(BufferSerializer<T> serializer) where T : IReaderWriter
+        {
+            serializer.SerializeValue(ref Str);
+            serializer.SerializeValue(ref Int);
+        }
+
+        public bool Equals(UnmanagedNetworkSerializableType other)
+        {
+            return Str.Equals(other.Str) && Int == other.Int;
+        }
+
+        public override bool Equals(object obj)
+        {
+            if (obj == null)
+            {
+                return false;
+            }
+
+            if (obj.GetType() != GetType())
+            {
+                return false;
+            }
+
+            return Equals((ManagedNetworkSerializableType)obj);
+        }
+
+        public override int GetHashCode()
+        {
+            return Str.GetHashCode() ^ Int.GetHashCode() ^ InMemoryValue.GetHashCode();
+        }
+    }
+
+
+    public struct UnmanagedTemplateNetworkSerializableType<T> : INetworkSerializable where T : unmanaged, INetworkSerializable
+    {
+        public T Value;
+
+        public void NetworkSerialize<TReaderWriterType>(BufferSerializer<TReaderWriterType> serializer) where TReaderWriterType : IReaderWriter
+        {
+            serializer.SerializeValue(ref Value);
+        }
+    }
+
+    public struct ManagedTemplateNetworkSerializableType<T> : INetworkSerializable where T : class, INetworkSerializable, new()
+    {
+        public T Value;
+
+        public void NetworkSerialize<TReaderWriterType>(BufferSerializer<TReaderWriterType> serializer) where TReaderWriterType : IReaderWriter
+        {
+            bool isNull = Value == null;
+            serializer.SerializeValue(ref isNull);
+            if (!isNull)
+            {
+                if (Value == null)
+                {
+                    Value = new T();
+                }
+                serializer.SerializeValue(ref Value);
+            }
+        }
+    }
+
     /// <summary>
     /// This provides coverage for all of the predefined NetworkVariable types
     /// The initial goal is for generalized full coverage of NetworkVariables:
@@ -30,6 +183,12 @@ namespace Unity.Netcode.RuntimeTests
         private NetworkVariable<ulong> m_NetworkVariableULong = new NetworkVariable<ulong>();
         private NetworkVariable<uint> m_NetworkVariableUInt = new NetworkVariable<uint>();
         private NetworkVariable<ushort> m_NetworkVariableUShort = new NetworkVariable<ushort>();
+        private NetworkVariable<FixedString32Bytes> m_NetworkVariableFixedString32 = new NetworkVariable<FixedString32Bytes>();
+        private NetworkVariable<FixedString64Bytes> m_NetworkVariableFixedString64 = new NetworkVariable<FixedString64Bytes>();
+        private NetworkVariable<FixedString128Bytes> m_NetworkVariableFixedString128 = new NetworkVariable<FixedString128Bytes>();
+        private NetworkVariable<FixedString512Bytes> m_NetworkVariableFixedString512 = new NetworkVariable<FixedString512Bytes>();
+        private NetworkVariable<FixedString4096Bytes> m_NetworkVariableFixedString4096 = new NetworkVariable<FixedString4096Bytes>();
+        private NetworkVariable<ManagedNetworkSerializableType> m_NetworkVariableManaged = new NetworkVariable<ManagedNetworkSerializableType>();
 
 
         public NetworkVariableHelper<bool> Bool_Var;
@@ -50,10 +209,15 @@ namespace Unity.Netcode.RuntimeTests
         public NetworkVariableHelper<ulong> Ulong_Var;
         public NetworkVariableHelper<uint> Uint_Var;
         public NetworkVariableHelper<ushort> Ushort_Var;
+        public NetworkVariableHelper<FixedString32Bytes> FixedString32_Var;
+        public NetworkVariableHelper<FixedString64Bytes> FixedString64_Var;
+        public NetworkVariableHelper<FixedString128Bytes> FixedString128_Var;
+        public NetworkVariableHelper<FixedString512Bytes> FixedString512_Var;
+        public NetworkVariableHelper<FixedString4096Bytes> FixedString4096_Var;
+        public NetworkVariableHelper<ManagedNetworkSerializableType> Managed_Var;
 
 
         public bool EnableTesting;
-        private bool m_Initialized;
         private bool m_FinishedTests;
         private bool m_ChangesAppliedToNetworkVariables;
 
@@ -81,6 +245,12 @@ namespace Unity.Netcode.RuntimeTests
             m_NetworkVariableULong = new NetworkVariable<ulong>();
             m_NetworkVariableUInt = new NetworkVariable<uint>();
             m_NetworkVariableUShort = new NetworkVariable<ushort>();
+            m_NetworkVariableFixedString32 = new NetworkVariable<FixedString32Bytes>();
+            m_NetworkVariableFixedString64 = new NetworkVariable<FixedString64Bytes>();
+            m_NetworkVariableFixedString128 = new NetworkVariable<FixedString128Bytes>();
+            m_NetworkVariableFixedString512 = new NetworkVariable<FixedString512Bytes>();
+            m_NetworkVariableFixedString4096 = new NetworkVariable<FixedString4096Bytes>();
+            m_NetworkVariableManaged = new NetworkVariable<ManagedNetworkSerializableType>();
 
 
             // NetworkVariable Value Type Constructor Test Coverage
@@ -102,6 +272,16 @@ namespace Unity.Netcode.RuntimeTests
             m_NetworkVariableULong = new NetworkVariable<ulong>(1);
             m_NetworkVariableUInt = new NetworkVariable<uint>(1);
             m_NetworkVariableUShort = new NetworkVariable<ushort>(1);
+            m_NetworkVariableFixedString32 = new NetworkVariable<FixedString32Bytes>("1234567890");
+            m_NetworkVariableFixedString64 = new NetworkVariable<FixedString64Bytes>("1234567890");
+            m_NetworkVariableFixedString128 = new NetworkVariable<FixedString128Bytes>("1234567890");
+            m_NetworkVariableFixedString512 = new NetworkVariable<FixedString512Bytes>("1234567890");
+            m_NetworkVariableFixedString4096 = new NetworkVariable<FixedString4096Bytes>("1234567890");
+            m_NetworkVariableManaged = new NetworkVariable<ManagedNetworkSerializableType>(new ManagedNetworkSerializableType
+            {
+                Str = "1234567890",
+                Ints = new[] { 1, 2, 3, 4, 5 }
+            });
 
             // Use this nifty class: NetworkVariableHelper
             // Tracks if NetworkVariable changed invokes the OnValueChanged callback for the given instance type
@@ -123,6 +303,12 @@ namespace Unity.Netcode.RuntimeTests
             Ulong_Var = new NetworkVariableHelper<ulong>(m_NetworkVariableULong);
             Uint_Var = new NetworkVariableHelper<uint>(m_NetworkVariableUInt);
             Ushort_Var = new NetworkVariableHelper<ushort>(m_NetworkVariableUShort);
+            FixedString32_Var = new NetworkVariableHelper<FixedString32Bytes>(m_NetworkVariableFixedString32);
+            FixedString64_Var = new NetworkVariableHelper<FixedString64Bytes>(m_NetworkVariableFixedString64);
+            FixedString128_Var = new NetworkVariableHelper<FixedString128Bytes>(m_NetworkVariableFixedString128);
+            FixedString512_Var = new NetworkVariableHelper<FixedString512Bytes>(m_NetworkVariableFixedString512);
+            FixedString4096_Var = new NetworkVariableHelper<FixedString4096Bytes>(m_NetworkVariableFixedString4096);
+            Managed_Var = new NetworkVariableHelper<ManagedNetworkSerializableType>(m_NetworkVariableManaged);
         }
 
         /// <summary>
@@ -148,6 +334,62 @@ namespace Unity.Netcode.RuntimeTests
             return m_FinishedTests;
         }
 
+        public void Awake()
+        {
+            InitializeTest();
+        }
+
+        public void AssertAllValuesAreCorrect()
+        {
+            Assert.AreEqual(false, m_NetworkVariableBool.Value);
+            Assert.AreEqual(255, m_NetworkVariableByte.Value);
+            Assert.AreEqual(100, m_NetworkVariableColor.Value.r);
+            Assert.AreEqual(100, m_NetworkVariableColor.Value.g);
+            Assert.AreEqual(100, m_NetworkVariableColor.Value.b);
+            Assert.AreEqual(100, m_NetworkVariableColor32.Value.r);
+            Assert.AreEqual(100, m_NetworkVariableColor32.Value.g);
+            Assert.AreEqual(100, m_NetworkVariableColor32.Value.b);
+            Assert.AreEqual(100, m_NetworkVariableColor32.Value.a);
+            Assert.AreEqual(1000, m_NetworkVariableDouble.Value);
+            Assert.AreEqual(1000.0f, m_NetworkVariableFloat.Value);
+            Assert.AreEqual(1000, m_NetworkVariableInt.Value);
+            Assert.AreEqual(100000, m_NetworkVariableLong.Value);
+            Assert.AreEqual(-127, m_NetworkVariableSByte.Value);
+            Assert.AreEqual(100, m_NetworkVariableQuaternion.Value.w);
+            Assert.AreEqual(100, m_NetworkVariableQuaternion.Value.x);
+            Assert.AreEqual(100, m_NetworkVariableQuaternion.Value.y);
+            Assert.AreEqual(100, m_NetworkVariableQuaternion.Value.z);
+            Assert.AreEqual(short.MaxValue, m_NetworkVariableShort.Value);
+            Assert.AreEqual(1000, m_NetworkVariableVector4.Value.w);
+            Assert.AreEqual(1000, m_NetworkVariableVector4.Value.x);
+            Assert.AreEqual(1000, m_NetworkVariableVector4.Value.y);
+            Assert.AreEqual(1000, m_NetworkVariableVector4.Value.z);
+            Assert.AreEqual(1000, m_NetworkVariableVector3.Value.x);
+            Assert.AreEqual(1000, m_NetworkVariableVector3.Value.y);
+            Assert.AreEqual(1000, m_NetworkVariableVector3.Value.z);
+            Assert.AreEqual(1000, m_NetworkVariableVector2.Value.x);
+            Assert.AreEqual(1000, m_NetworkVariableVector2.Value.y);
+            Assert.AreEqual(Vector3.one.x, m_NetworkVariableRay.Value.origin.x);
+            Assert.AreEqual(Vector3.one.y, m_NetworkVariableRay.Value.origin.y);
+            Assert.AreEqual(Vector3.one.z, m_NetworkVariableRay.Value.origin.z);
+            Assert.AreEqual(Vector3.right.x, m_NetworkVariableRay.Value.direction.x);
+            Assert.AreEqual(Vector3.right.y, m_NetworkVariableRay.Value.direction.y);
+            Assert.AreEqual(Vector3.right.z, m_NetworkVariableRay.Value.direction.z);
+            Assert.AreEqual(ulong.MaxValue, m_NetworkVariableULong.Value);
+            Assert.AreEqual(uint.MaxValue, m_NetworkVariableUInt.Value);
+            Assert.AreEqual(ushort.MaxValue, m_NetworkVariableUShort.Value);
+            Assert.IsTrue(m_NetworkVariableFixedString32.Value.Equals("FixedString32Bytes"));
+            Assert.IsTrue(m_NetworkVariableFixedString64.Value.Equals("FixedString64Bytes"));
+            Assert.IsTrue(m_NetworkVariableFixedString128.Value.Equals("FixedString128Bytes"));
+            Assert.IsTrue(m_NetworkVariableFixedString512.Value.Equals("FixedString512Bytes"));
+            Assert.IsTrue(m_NetworkVariableFixedString4096.Value.Equals("FixedString4096Bytes"));
+            Assert.IsTrue(m_NetworkVariableManaged.Value.Equals(new ManagedNetworkSerializableType
+            {
+                Str = "ManagedNetworkSerializableType",
+                Ints = new[] { 1000, 2000, 3000, 4000, 5000, 6000, 7000, 8000, 9000, 10000 }
+            }));
+        }
+
         // Update is called once per frame
         private void Update()
         {
@@ -164,37 +406,39 @@ namespace Unity.Netcode.RuntimeTests
                 {
                     if (NetworkManager != null && NetworkManager.IsListening)
                     {
-                        if (!m_Initialized)
+                        //Now change all of the values to make sure we are at least testing the local callback
+                        m_NetworkVariableBool.Value = false;
+                        m_NetworkVariableByte.Value = 255;
+                        m_NetworkVariableColor.Value = new Color(100, 100, 100);
+                        m_NetworkVariableColor32.Value = new Color32(100, 100, 100, 100);
+                        m_NetworkVariableDouble.Value = 1000;
+                        m_NetworkVariableFloat.Value = 1000.0f;
+                        m_NetworkVariableInt.Value = 1000;
+                        m_NetworkVariableLong.Value = 100000;
+                        m_NetworkVariableSByte.Value = -127;
+                        m_NetworkVariableQuaternion.Value = new Quaternion(100, 100, 100, 100);
+                        m_NetworkVariableShort.Value = short.MaxValue;
+                        m_NetworkVariableVector4.Value = new Vector4(1000, 1000, 1000, 1000);
+                        m_NetworkVariableVector3.Value = new Vector3(1000, 1000, 1000);
+                        m_NetworkVariableVector2.Value = new Vector2(1000, 1000);
+                        m_NetworkVariableRay.Value = new Ray(Vector3.one, Vector3.right);
+                        m_NetworkVariableULong.Value = ulong.MaxValue;
+                        m_NetworkVariableUInt.Value = uint.MaxValue;
+                        m_NetworkVariableUShort.Value = ushort.MaxValue;
+                        m_NetworkVariableFixedString32.Value = new FixedString32Bytes("FixedString32Bytes");
+                        m_NetworkVariableFixedString64.Value = new FixedString64Bytes("FixedString64Bytes");
+                        m_NetworkVariableFixedString128.Value = new FixedString128Bytes("FixedString128Bytes");
+                        m_NetworkVariableFixedString512.Value = new FixedString512Bytes("FixedString512Bytes");
+                        m_NetworkVariableFixedString4096.Value = new FixedString4096Bytes("FixedString4096Bytes");
+                        m_NetworkVariableManaged.Value = new ManagedNetworkSerializableType
                         {
-                            InitializeTest();
-                            m_Initialized = true;
-                        }
-                        else
-                        {
-                            //Now change all of the values to make sure we are at least testing the local callback
-                            m_NetworkVariableBool.Value = false;
-                            m_NetworkVariableByte.Value = 255;
-                            m_NetworkVariableColor.Value = new Color(100, 100, 100);
-                            m_NetworkVariableColor32.Value = new Color32(100, 100, 100, 100);
-                            m_NetworkVariableDouble.Value = 1000;
-                            m_NetworkVariableFloat.Value = 1000.0f;
-                            m_NetworkVariableInt.Value = 1000;
-                            m_NetworkVariableLong.Value = 100000;
-                            m_NetworkVariableSByte.Value = -127;
-                            m_NetworkVariableQuaternion.Value = new Quaternion(100, 100, 100, 100);
-                            m_NetworkVariableShort.Value = short.MaxValue;
-                            m_NetworkVariableVector4.Value = new Vector4(1000, 1000, 1000, 1000);
-                            m_NetworkVariableVector3.Value = new Vector3(1000, 1000, 1000);
-                            m_NetworkVariableVector2.Value = new Vector2(1000, 1000);
-                            m_NetworkVariableRay.Value = new Ray(Vector3.one, Vector3.right);
-                            m_NetworkVariableULong.Value = ulong.MaxValue;
-                            m_NetworkVariableUInt.Value = uint.MaxValue;
-                            m_NetworkVariableUShort.Value = ushort.MaxValue;
+                            Str = "ManagedNetworkSerializableType",
+                            Ints = new[] { 1000, 2000, 3000, 4000, 5000, 6000, 7000, 8000, 9000, 10000 }
+                        };
 
-                            //Set the timeout (i.e. how long we will wait for all NetworkVariables to have registered their changes)
-                            m_WaitForChangesTimeout = Time.realtimeSinceStartup + 0.50f;
-                            m_ChangesAppliedToNetworkVariables = true;
-                        }
+                        //Set the timeout (i.e. how long we will wait for all NetworkVariables to have registered their changes)
+                        m_WaitForChangesTimeout = Time.realtimeSinceStartup + 0.50f;
+                        m_ChangesAppliedToNetworkVariables = true;
                     }
                 }
             }

Tests/Runtime/ConnectionApproval.cs

@@ -62,11 +62,27 @@ namespace Unity.Netcode.RuntimeTests
             response.PlayerPrefabHash = null;
         }
 
+
+        [Test]
+        public void VerifyUniqueNetworkConfigPerRequest()
+        {
+            var networkConfig = new NetworkConfig();
+            networkConfig.EnableSceneManagement = true;
+            networkConfig.TickRate = 30;
+            var currentHash = networkConfig.GetConfig();
+            networkConfig.EnableSceneManagement = false;
+            networkConfig.TickRate = 60;
+            var newHash = networkConfig.GetConfig(false);
+
+            Assert.True(currentHash != newHash, $"Hashed {nameof(NetworkConfig)} values {currentHash} and {newHash} should not be the same!");
+        }
+
         [TearDown]
         public void TearDown()
         {
             // Stop, shutdown, and destroy
             NetworkManagerHelper.ShutdownNetworkManager();
         }
+
     }
 }

Tests/Runtime/ConnectionApprovalTimeoutTests.cs

@@ -0,0 +1,101 @@
+using System.Collections;
+using System.Text.RegularExpressions;
+using NUnit.Framework;
+using Unity.Netcode.TestHelpers.Runtime;
+using UnityEngine;
+using UnityEngine.TestTools;
+
+namespace Unity.Netcode.RuntimeTests
+{
+    [TestFixture(ApprovalTimedOutTypes.ServerDoesNotRespond)]
+    [TestFixture(ApprovalTimedOutTypes.ClientDoesNotRequest)]
+    public class ConnectionApprovalTimeoutTests : NetcodeIntegrationTest
+    {
+        protected override int NumberOfClients => 1;
+
+        public enum ApprovalTimedOutTypes
+        {
+            ClientDoesNotRequest,
+            ServerDoesNotRespond
+        }
+
+        private ApprovalTimedOutTypes m_ApprovalFailureType;
+
+        public ConnectionApprovalTimeoutTests(ApprovalTimedOutTypes approvalFailureType)
+        {
+            m_ApprovalFailureType = approvalFailureType;
+        }
+
+        // Must be >= 2 since this is an int value and the test waits for timeout - 1 to try to verify it doesn't
+        // time out early
+        private const int k_TestTimeoutPeriod = 1;
+
+        private Regex m_ExpectedLogMessage;
+        private LogType m_LogType;
+
+
+        protected override IEnumerator OnSetup()
+        {
+            m_BypassConnectionTimeout = true;
+            return base.OnSetup();
+        }
+
+        protected override IEnumerator OnTearDown()
+        {
+            m_BypassConnectionTimeout = false;
+            return base.OnTearDown();
+        }
+
+        protected override void OnServerAndClientsCreated()
+        {
+            m_ServerNetworkManager.NetworkConfig.ClientConnectionBufferTimeout = k_TestTimeoutPeriod;
+            m_ServerNetworkManager.LogLevel = LogLevel.Developer;
+            m_ClientNetworkManagers[0].NetworkConfig.ClientConnectionBufferTimeout = k_TestTimeoutPeriod;
+            m_ClientNetworkManagers[0].LogLevel = LogLevel.Developer;
+            base.OnServerAndClientsCreated();
+        }
+
+        protected override IEnumerator OnStartedServerAndClients()
+        {
+            if (m_ApprovalFailureType == ApprovalTimedOutTypes.ServerDoesNotRespond)
+            {
+                // We catch (don't process) the incoming approval message to simulate the server not sending the approved message in time
+                m_ClientNetworkManagers[0].MessagingSystem.Hook(new MessageCatcher<ConnectionApprovedMessage>(m_ClientNetworkManagers[0]));
+                m_ExpectedLogMessage = new Regex("Timed out waiting for the server to approve the connection request.");
+                m_LogType = LogType.Log;
+            }
+            else
+            {
+                // We catch (don't process) the incoming connection request message to simulate a transport connection but the client never
+                // sends (or takes too long to send) the connection request.
+                m_ServerNetworkManager.MessagingSystem.Hook(new MessageCatcher<ConnectionRequestMessage>(m_ServerNetworkManager));
+
+                // For this test, we know the timed out client will be Client-1
+                m_ExpectedLogMessage = new Regex("Server detected a transport connection from Client-1, but timed out waiting for the connection request message.");
+                m_LogType = LogType.Warning;
+            }
+            yield return null;
+        }
+
+        [UnityTest]
+        public IEnumerator ValidateApprovalTimeout()
+        {
+            // Delay for half of the wait period
+            yield return new WaitForSeconds(k_TestTimeoutPeriod * 0.5f);
+
+            // Verify we haven't received the time out message yet
+            NetcodeLogAssert.LogWasNotReceived(LogType.Log, m_ExpectedLogMessage);
+
+            // Wait for 3/4s of the time out period to pass (totaling 1.25x the wait period)
+            yield return new WaitForSeconds(k_TestTimeoutPeriod * 0.75f);
+
+            // We should have the test relative log message by this time.
+            NetcodeLogAssert.LogWasReceived(m_LogType, m_ExpectedLogMessage);
+
+            // It should only have the host client connected
+            Assert.AreEqual(1, m_ServerNetworkManager.ConnectedClients.Count, $"Expected only one client when there were {m_ServerNetworkManager.ConnectedClients.Count} clients connected!");
+            Assert.AreEqual(0, m_ServerNetworkManager.PendingClients.Count, $"Expected no pending clients when there were {m_ServerNetworkManager.PendingClients.Count} pending clients!");
+            Assert.True(!m_ClientNetworkManagers[0].IsApproved, $"Expected the client to not have been approved, but it was!");
+        }
+    }
+}

Tests/Runtime/ConnectionApprovalTimeoutTests.cs.meta

@@ -0,0 +1,3 @@
+fileFormatVersion: 2
+guid: b0c4159ea234415fa9497860e6ef4fc2
+timeCreated: 1661796642

Tests/Runtime/DeferredMessagingTests.cs

@@ -1,8 +1,8 @@
 using System;
 using System.Collections;
 using System.Collections.Generic;
+using System.Linq;
 using NUnit.Framework;
-using Unity.Collections;
 using UnityEngine;
 using UnityEngine.TestTools;
 using Unity.Netcode.TestHelpers.Runtime;
@@ -113,82 +113,6 @@ namespace Unity.Netcode.RuntimeTests
         }
     }
 
-    internal class SpawnCatcher : INetworkHooks
-    {
-        public struct TriggerData
-        {
-            public FastBufferReader Reader;
-            public MessageHeader Header;
-            public ulong SenderId;
-            public float Timestamp;
-            public int SerializedHeaderSize;
-        }
-        public readonly List<TriggerData> CaughtMessages = new List<TriggerData>();
-
-        public void OnBeforeSendMessage<T>(ulong clientId, ref T message, NetworkDelivery delivery) where T : INetworkMessage
-        {
-        }
-
-        public void OnAfterSendMessage<T>(ulong clientId, ref T message, NetworkDelivery delivery, int messageSizeBytes) where T : INetworkMessage
-        {
-        }
-
-        public void OnBeforeReceiveMessage(ulong senderId, Type messageType, int messageSizeBytes)
-        {
-        }
-
-        public void OnAfterReceiveMessage(ulong senderId, Type messageType, int messageSizeBytes)
-        {
-        }
-
-        public void OnBeforeSendBatch(ulong clientId, int messageCount, int batchSizeInBytes, NetworkDelivery delivery)
-        {
-        }
-
-        public void OnAfterSendBatch(ulong clientId, int messageCount, int batchSizeInBytes, NetworkDelivery delivery)
-        {
-        }
-
-        public void OnBeforeReceiveBatch(ulong senderId, int messageCount, int batchSizeInBytes)
-        {
-        }
-
-        public void OnAfterReceiveBatch(ulong senderId, int messageCount, int batchSizeInBytes)
-        {
-        }
-
-        public bool OnVerifyCanSend(ulong destinationId, Type messageType, NetworkDelivery delivery)
-        {
-            return true;
-        }
-
-        public bool OnVerifyCanReceive(ulong senderId, Type messageType, FastBufferReader messageContent, ref NetworkContext context)
-        {
-            if (messageType == typeof(CreateObjectMessage))
-            {
-                CaughtMessages.Add(new TriggerData
-                {
-                    Reader = new FastBufferReader(messageContent, Allocator.Persistent),
-                    Header = context.Header,
-                    Timestamp = context.Timestamp,
-                    SenderId = context.SenderId,
-                    SerializedHeaderSize = context.SerializedHeaderSize
-                });
-                return false;
-            }
-
-            return true;
-        }
-
-        public void OnBeforeHandleMessage<T>(ref T message, ref NetworkContext context) where T : INetworkMessage
-        {
-        }
-
-        public void OnAfterHandleMessage<T>(ref T message, ref NetworkContext context) where T : INetworkMessage
-        {
-        }
-    }
-
     public class DeferredMessageTestRpcComponent : NetworkBehaviour
     {
         public bool ClientRpcCalled;
@@ -198,62 +122,87 @@ namespace Unity.Netcode.RuntimeTests
         {
             ClientRpcCalled = true;
         }
+
+        public static readonly List<ulong> ClientInstances = new List<ulong>();
+        public override void OnNetworkSpawn()
+        {
+            if (!IsServer)
+            {
+                ClientInstances.Add(NetworkManager.LocalClientId);
+            }
+            base.OnNetworkSpawn();
+        }
     }
 
     public class DeferredMessageTestNetworkVariableComponent : NetworkBehaviour
     {
-        public NetworkVariable<int> TestNetworkVariable = new NetworkVariable<int>();
+        public static readonly List<ulong> ClientInstances = new List<ulong>();
+
+        public NetworkVariable<int> TestNetworkVariable;
+
+        public void Awake()
+        {
+            TestNetworkVariable = new NetworkVariable<int>(default, NetworkVariableReadPermission.Everyone, NetworkVariableWritePermission.Owner);
+        }
+
+        public override void OnNetworkSpawn()
+        {
+            if (!IsServer)
+            {
+                ClientInstances.Add(NetworkManager.LocalClientId);
+            }
+            base.OnNetworkSpawn();
+        }
     }
 
     public class DeferredMessageTestRpcAndNetworkVariableComponent : NetworkBehaviour
     {
+        public static readonly List<ulong> ClientInstances = new List<ulong>();
         public bool ClientRpcCalled;
+        public NetworkVariable<int> TestNetworkVariable;
+
+        public void Awake()
+        {
+            TestNetworkVariable = new NetworkVariable<int>(default, NetworkVariableReadPermission.Everyone, NetworkVariableWritePermission.Owner);
+        }
+
+        public override void OnNetworkSpawn()
+        {
+            if (!IsServer)
+            {
+                ClientInstances.Add(NetworkManager.LocalClientId);
+            }
+            base.OnNetworkSpawn();
+        }
 
         [ClientRpc]
         public void SendTestClientRpc()
         {
             ClientRpcCalled = true;
         }
-
-        public NetworkVariable<int> TestNetworkVariable = new NetworkVariable<int>();
     }
 
     public class DeferredMessagingTest : NetcodeIntegrationTest
     {
-        protected override int NumberOfClients => 2;
+        protected override int NumberOfClients => 0;
 
-        private List<SpawnCatcher> m_ClientSpawnCatchers = new List<SpawnCatcher>();
+        private List<MessageCatcher<CreateObjectMessage>> m_ClientSpawnCatchers = new List<MessageCatcher<CreateObjectMessage>>();
 
         private GameObject m_RpcPrefab;
         private GameObject m_NetworkVariablePrefab;
         private GameObject m_RpcAndNetworkVariablePrefab;
 
+        private int m_NumberOfClientsToLateJoin = 2;
+
         protected override IEnumerator OnSetup()
         {
+            DeferredMessageTestRpcAndNetworkVariableComponent.ClientInstances.Clear();
+            DeferredMessageTestRpcComponent.ClientInstances.Clear();
+            DeferredMessageTestNetworkVariableComponent.ClientInstances.Clear();
+            m_SkipAddingPrefabsToClient = false;
             // Host is irrelevant, messages don't get sent to the host "client"
             m_UseHost = false;
 
-            m_RpcPrefab = new GameObject("Object With RPC");
-            var networkObject = m_RpcPrefab.AddComponent<NetworkObject>();
-            m_RpcPrefab.AddComponent<DeferredMessageTestRpcComponent>();
-
-            // Make it a prefab
-            NetcodeIntegrationTestHelpers.MakeNetworkObjectTestPrefab(networkObject);
-
-            m_NetworkVariablePrefab = new GameObject("Object With NetworkVariable");
-            networkObject = m_NetworkVariablePrefab.AddComponent<NetworkObject>();
-            m_NetworkVariablePrefab.AddComponent<DeferredMessageTestNetworkVariableComponent>();
-
-            // Make it a prefab
-            NetcodeIntegrationTestHelpers.MakeNetworkObjectTestPrefab(networkObject);
-
-            m_RpcAndNetworkVariablePrefab = new GameObject("Object With NetworkVariable And RPC");
-            networkObject = m_RpcAndNetworkVariablePrefab.AddComponent<NetworkObject>();
-            m_RpcAndNetworkVariablePrefab.AddComponent<DeferredMessageTestRpcAndNetworkVariableComponent>();
-
-            // Make it a prefab
-            NetcodeIntegrationTestHelpers.MakeNetworkObjectTestPrefab(networkObject);
-
             // Replace the IDeferredMessageManager component with our test one in the component factory
             ComponentFactory.Register<IDeferredMessageManager>(networkManager => new TestDeferredMessageManager(networkManager));
             yield return null;
@@ -269,13 +218,54 @@ namespace Unity.Netcode.RuntimeTests
 
         protected override void OnServerAndClientsCreated()
         {
-            m_ServerNetworkManager.AddNetworkPrefab(m_RpcPrefab);
-            m_ServerNetworkManager.AddNetworkPrefab(m_NetworkVariablePrefab);
-            m_ServerNetworkManager.AddNetworkPrefab(m_RpcAndNetworkVariablePrefab);
+            // Note: This is where prefabs should be created
+            m_RpcPrefab = CreateNetworkObjectPrefab("Object With RPC");
+            var networkObject = m_RpcPrefab.GetComponent<NetworkObject>();
+            m_RpcPrefab.AddComponent<DeferredMessageTestRpcComponent>();
+
+            m_NetworkVariablePrefab = CreateNetworkObjectPrefab("Object With NetworkVariable");
+            networkObject = m_NetworkVariablePrefab.GetComponent<NetworkObject>();
+            m_NetworkVariablePrefab.AddComponent<DeferredMessageTestNetworkVariableComponent>();
+
+            m_RpcAndNetworkVariablePrefab = CreateNetworkObjectPrefab("Object With NetworkVariable And RPC");
+            networkObject = m_RpcAndNetworkVariablePrefab.GetComponent<NetworkObject>();
+            m_RpcAndNetworkVariablePrefab.AddComponent<DeferredMessageTestRpcAndNetworkVariableComponent>();
+
             m_ServerNetworkManager.NetworkConfig.ForceSamePrefabs = false;
-            foreach (var client in m_ClientNetworkManagers)
+
+        }
+
+        private bool m_SkipAddingPrefabsToClient = false;
+
+        private void AddPrefabsToClient(NetworkManager networkManager)
+        {
+            networkManager.AddNetworkPrefab(m_RpcPrefab);
+            networkManager.AddNetworkPrefab(m_NetworkVariablePrefab);
+            networkManager.AddNetworkPrefab(m_RpcAndNetworkVariablePrefab);
+        }
+
+        protected override void OnNewClientCreated(NetworkManager networkManager)
+        {
+            networkManager.NetworkConfig.ForceSamePrefabs = false;
+            if (!m_SkipAddingPrefabsToClient)
             {
-                client.NetworkConfig.ForceSamePrefabs = false;
+                AddPrefabsToClient(networkManager);
+            }
+
+            base.OnNewClientCreated(networkManager);
+        }
+
+        private IEnumerator SpawnClients(bool clearTestDeferredMessageManagerCallFlags = true)
+        {
+            for (int i = 0; i < m_NumberOfClientsToLateJoin; i++)
+            {
+                // Create and join client
+                yield return CreateAndStartNewClient();
+            }
+
+            if (clearTestDeferredMessageManagerCallFlags)
+            {
+                ClearTestDeferredMessageManagerCallFlags();
             }
         }
 
@@ -296,38 +286,19 @@ namespace Unity.Netcode.RuntimeTests
         {
             foreach (var client in m_ClientNetworkManagers)
             {
-                var catcher = new SpawnCatcher();
+                var catcher = new MessageCatcher<CreateObjectMessage>(client);
                 m_ClientSpawnCatchers.Add(catcher);
                 client.MessagingSystem.Hook(catcher);
             }
         }
 
-        private void RegisterClientPrefabs(bool clearTestDeferredMessageManagerCallFlags = true)
-        {
-            foreach (var client in m_ClientNetworkManagers)
-            {
-                client.AddNetworkPrefab(m_RpcPrefab);
-                client.AddNetworkPrefab(m_NetworkVariablePrefab);
-                client.AddNetworkPrefab(m_RpcAndNetworkVariablePrefab);
-            }
-
-            if (clearTestDeferredMessageManagerCallFlags)
-            {
-                ClearTestDeferredMessageManagerCallFlags();
-            }
-        }
-
         private void ReleaseSpawns()
         {
             for (var i = 0; i < m_ClientNetworkManagers.Length; ++i)
             {
                 // Unhook first so the spawn catcher stops catching spawns
                 m_ClientNetworkManagers[i].MessagingSystem.Unhook(m_ClientSpawnCatchers[i]);
-                foreach (var caughtSpawn in m_ClientSpawnCatchers[i].CaughtMessages)
-                {
-                    // Reader will be disposed within HandleMessage
-                    m_ClientNetworkManagers[i].MessagingSystem.HandleMessage(caughtSpawn.Header, caughtSpawn.Reader, caughtSpawn.SenderId, caughtSpawn.Timestamp, caughtSpawn.SerializedHeaderSize);
-                }
+                m_ClientSpawnCatchers[i].ReleaseMessages();
             }
             m_ClientSpawnCatchers.Clear();
         }
@@ -345,7 +316,7 @@ namespace Unity.Netcode.RuntimeTests
             {
                 foreach (var catcher in m_ClientSpawnCatchers)
                 {
-                    if (catcher.CaughtMessages.Count != count)
+                    if (catcher.CaughtMessageCount != count)
                     {
                         return false;
                     }
@@ -372,89 +343,54 @@ namespace Unity.Netcode.RuntimeTests
             Assert.AreEqual(0, manager.DeferredMessageCountForType(IDeferredMessageManager.TriggerType.OnAddPrefab));
         }
 
-        private static CoroutineRunner s_CoroutineRunner;
-
-        private Coroutine Run(IEnumerator enumerator)
+        private IEnumerator WaitForAllClientsToReceive<T>() where T : INetworkMessage
         {
-            if (s_CoroutineRunner == null)
-            {
-                s_CoroutineRunner = new GameObject(nameof(CoroutineRunner)).AddComponent<CoroutineRunner>();
-            }
-
-            return s_CoroutineRunner.StartCoroutine(enumerator);
+            yield return WaitForMessageReceived<T>(m_ClientNetworkManagers.ToList(), ReceiptType.Received);
         }
 
-        private IEnumerator RunMultiple(List<IEnumerator> waitFor)
-        {
-            yield return WaitMultiple(StartMultiple(waitFor));
-        }
-
-        private List<Coroutine> StartMultiple(List<IEnumerator> waitFor)
-        {
-            var runningCoroutines = new List<Coroutine>();
-            foreach (var enumerator in waitFor)
-            {
-                runningCoroutines.Add(Run(enumerator));
-            }
-
-            return runningCoroutines;
-        }
-
-        private IEnumerator WaitMultiple(List<Coroutine> runningCoroutines)
-        {
-            foreach (var coroutine in runningCoroutines)
-            {
-                yield return coroutine;
-            }
-        }
-
-        private List<IEnumerator> WaitForAllClientsToReceive<T>() where T : INetworkMessage
-        {
-            var waiters = new List<IEnumerator>();
-            foreach (var client in m_ClientNetworkManagers)
-            {
-                waiters.Add(NetcodeIntegrationTestHelpers.WaitForMessageOfTypeReceived<T>(client));
-            }
-
-            return waiters;
-        }
-
-        private List<IEnumerator> WaitForAllClientsToReceive<TFirstMessage, TSecondMessage>()
+        private IEnumerator WaitForAllClientsToReceive<TFirstMessage, TSecondMessage>()
             where TFirstMessage : INetworkMessage
             where TSecondMessage : INetworkMessage
         {
-            var waiters = new List<IEnumerator>();
-            foreach (var client in m_ClientNetworkManagers)
+            yield return WaitForMessagesReceived(new List<Type>
             {
-                waiters.Add(NetcodeIntegrationTestHelpers.WaitForMessageOfTypeReceived<TFirstMessage>(client));
-                waiters.Add(NetcodeIntegrationTestHelpers.WaitForMessageOfTypeReceived<TSecondMessage>(client));
-            }
-
-            return waiters;
+                typeof(TFirstMessage),
+                typeof(TSecondMessage)
+            }, m_ClientNetworkManagers.ToList(), ReceiptType.Received);
         }
 
-        private List<IEnumerator> WaitForAllClientsToReceive<TFirstMessage, TSecondMessage, TThirdMessage, TFourthMessage>()
+        private IEnumerator WaitForAllClientsToReceive<TFirstMessage, TSecondMessage, TThirdMessage>()
+        where TFirstMessage : INetworkMessage
+        where TSecondMessage : INetworkMessage
+        where TThirdMessage : INetworkMessage
+        {
+            yield return WaitForMessagesReceived(new List<Type>
+            {
+                typeof(TFirstMessage),
+                typeof(TSecondMessage),
+                typeof(TThirdMessage),
+            }, m_ClientNetworkManagers.ToList(), ReceiptType.Received);
+        }
+
+        private IEnumerator WaitForAllClientsToReceive<TFirstMessage, TSecondMessage, TThirdMessage, TFourthMessage>()
             where TFirstMessage : INetworkMessage
             where TSecondMessage : INetworkMessage
             where TThirdMessage : INetworkMessage
             where TFourthMessage : INetworkMessage
         {
-            var waiters = new List<IEnumerator>();
-            foreach (var client in m_ClientNetworkManagers)
+            yield return WaitForMessagesReceived(new List<Type>
             {
-                waiters.Add(NetcodeIntegrationTestHelpers.WaitForMessageOfTypeReceived<TFirstMessage>(client));
-                waiters.Add(NetcodeIntegrationTestHelpers.WaitForMessageOfTypeReceived<TSecondMessage>(client));
-                waiters.Add(NetcodeIntegrationTestHelpers.WaitForMessageOfTypeReceived<TThirdMessage>(client));
-                waiters.Add(NetcodeIntegrationTestHelpers.WaitForMessageOfTypeReceived<TFourthMessage>(client));
-            }
-
-            return waiters;
+                typeof(TFirstMessage),
+                typeof(TSecondMessage),
+                typeof(TThirdMessage),
+                typeof(TFourthMessage),
+            }, m_ClientNetworkManagers.ToList(), ReceiptType.Received);
         }
 
         [UnityTest]
         public IEnumerator WhenAnRpcArrivesBeforeASpawnArrives_ItIsDeferred()
         {
-            RegisterClientPrefabs();
+            yield return SpawnClients();
             CatchSpawns();
             var serverObject = Object.Instantiate(m_RpcPrefab);
             serverObject.GetComponent<NetworkObject>().NetworkManagerOwner = m_ServerNetworkManager;
@@ -463,7 +399,7 @@ namespace Unity.Netcode.RuntimeTests
 
             serverObject.GetComponent<DeferredMessageTestRpcComponent>().SendTestClientRpc();
 
-            yield return RunMultiple(WaitForAllClientsToReceive<ClientRpcMessage>());
+            yield return WaitForAllClientsToReceive<ClientRpcMessage>();
 
             foreach (var client in m_ClientNetworkManagers)
             {
@@ -477,7 +413,7 @@ namespace Unity.Netcode.RuntimeTests
         [UnityTest]
         public IEnumerator WhenADespawnArrivesBeforeASpawnArrives_ItIsDeferred()
         {
-            RegisterClientPrefabs();
+            yield return SpawnClients();
             CatchSpawns();
             var serverObject = Object.Instantiate(m_RpcPrefab);
             serverObject.GetComponent<NetworkObject>().NetworkManagerOwner = m_ServerNetworkManager;
@@ -486,7 +422,7 @@ namespace Unity.Netcode.RuntimeTests
 
             serverObject.GetComponent<NetworkObject>().Despawn(false);
 
-            yield return RunMultiple(WaitForAllClientsToReceive<DestroyObjectMessage>());
+            yield return WaitForAllClientsToReceive<DestroyObjectMessage>();
 
             foreach (var client in m_ClientNetworkManagers)
             {
@@ -500,7 +436,7 @@ namespace Unity.Netcode.RuntimeTests
         [UnityTest]
         public IEnumerator WhenAChangeOwnershipMessageArrivesBeforeASpawnArrives_ItIsDeferred()
         {
-            RegisterClientPrefabs();
+            yield return SpawnClients();
             CatchSpawns();
             var serverObject = Object.Instantiate(m_RpcPrefab);
             serverObject.GetComponent<NetworkObject>().NetworkManagerOwner = m_ServerNetworkManager;
@@ -508,7 +444,7 @@ namespace Unity.Netcode.RuntimeTests
             yield return WaitForClientsToCatchSpawns();
 
             serverObject.GetComponent<NetworkObject>().ChangeOwnership(m_ClientNetworkManagers[0].LocalClientId);
-            yield return RunMultiple(WaitForAllClientsToReceive<ChangeOwnershipMessage>());
+            yield return WaitForAllClientsToReceive<ChangeOwnershipMessage>();
             foreach (var client in m_ClientNetworkManagers)
             {
                 var manager = (TestDeferredMessageManager)client.DeferredMessageManager;
@@ -521,13 +457,10 @@ namespace Unity.Netcode.RuntimeTests
         [UnityTest]
         public IEnumerator WhenANetworkVariableDeltaMessageArrivesBeforeASpawnArrives_ItIsDeferred()
         {
-            RegisterClientPrefabs();
+            m_SkipAddingPrefabsToClient = true;
+            yield return SpawnClients();
             CatchSpawns();
 
-            // Have to start these before spawning here because spawning sends a NetworkVariableDeltaMessage, too
-            // Depending on timing, if we start this after spawning, we may end up missing the first one.
-            var waiters = WaitForAllClientsToReceive<NetworkVariableDeltaMessage, NetworkVariableDeltaMessage>();
-            var coroutines = StartMultiple(waiters);
 
             var serverObject = Object.Instantiate(m_NetworkVariablePrefab);
             serverObject.GetComponent<NetworkObject>().NetworkManagerOwner = m_ServerNetworkManager;
@@ -536,7 +469,7 @@ namespace Unity.Netcode.RuntimeTests
 
             serverObject.GetComponent<DeferredMessageTestNetworkVariableComponent>().TestNetworkVariable.Value = 1;
 
-            yield return WaitMultiple(coroutines);
+            yield return WaitForAllClientsToReceive<NetworkVariableDeltaMessage>();
 
             foreach (var client in m_ClientNetworkManagers)
             {
@@ -545,18 +478,21 @@ namespace Unity.Netcode.RuntimeTests
                 Assert.IsFalse(manager.ProcessTriggersCalled);
                 // TODO: Network Variables generate an extra message immediately at spawn for some reason...
                 // Seems like a bug since the network variable data is in the spawn message already.
-                AssertSpawnTriggerCountForObject(manager, serverObject, 2);
+                AssertSpawnTriggerCountForObject(manager, serverObject, 1);
             }
         }
 
         [UnityTest]
+        //[Ignore("Disabling this temporarily until it is migrated into new integration test.")]
         public IEnumerator WhenASpawnMessageArrivesBeforeThePrefabIsAvailable_ItIsDeferred()
         {
+            m_SkipAddingPrefabsToClient = true;
+            yield return SpawnClients();
             var serverObject = Object.Instantiate(m_RpcPrefab);
             serverObject.GetComponent<NetworkObject>().NetworkManagerOwner = m_ServerNetworkManager;
             serverObject.GetComponent<NetworkObject>().Spawn();
 
-            yield return RunMultiple(WaitForAllClientsToReceive<CreateObjectMessage>());
+            yield return WaitForAllClientsToReceive<CreateObjectMessage>();
 
             foreach (var client in m_ClientNetworkManagers)
             {
@@ -631,8 +567,28 @@ namespace Unity.Netcode.RuntimeTests
         public IEnumerator WhenANetworkVariableDeltaMessageIsDeferred_ItIsProcessedOnSpawn()
         {
             yield return WhenANetworkVariableDeltaMessageArrivesBeforeASpawnArrives_ItIsDeferred();
+
+            foreach (var client in m_ClientNetworkManagers)
+            {
+                AddPrefabsToClient(client);
+            }
+
             ReleaseSpawns();
 
+            // Wait for the clients to spawn the NetworkObjects
+            bool HaveAllClientsSpawned()
+            {
+                foreach (var client in m_ClientNetworkManagers)
+                {
+                    if (!DeferredMessageTestNetworkVariableComponent.ClientInstances.Contains(client.LocalClientId))
+                    {
+                        return false;
+                    }
+                }
+                return true;
+            }
+            yield return WaitForConditionOrTimeOut(HaveAllClientsSpawned);
+
             foreach (var client in m_ClientNetworkManagers)
             {
                 var manager = (TestDeferredMessageManager)client.DeferredMessageManager;
@@ -647,9 +603,31 @@ namespace Unity.Netcode.RuntimeTests
         [UnityTest]
         public IEnumerator WhenASpawnMessageIsDeferred_ItIsProcessedOnAddPrefab()
         {
+            // This will prevent spawned clients from adding prefabs
+            m_SkipAddingPrefabsToClient = true;
             yield return WhenASpawnMessageArrivesBeforeThePrefabIsAvailable_ItIsDeferred();
-            RegisterClientPrefabs(false);
 
+            // Now add the prefabs
+            foreach (var client in m_ClientNetworkManagers)
+            {
+                AddPrefabsToClient(client);
+            }
+
+            // Wait for the clients to spawn the NetworkObjects
+            bool HaveAllClientsSpawned()
+            {
+                foreach (var client in m_ClientNetworkManagers)
+                {
+                    if (!DeferredMessageTestRpcComponent.ClientInstances.Contains(client.LocalClientId))
+                    {
+                        return false;
+                    }
+                }
+                return true;
+            }
+            yield return WaitForConditionOrTimeOut(HaveAllClientsSpawned);
+
+            // Validate this test
             foreach (var client in m_ClientNetworkManagers)
             {
                 var manager = (TestDeferredMessageManager)client.DeferredMessageManager;
@@ -664,14 +642,10 @@ namespace Unity.Netcode.RuntimeTests
         [UnityTest]
         public IEnumerator WhenMultipleSpawnTriggeredMessagesAreDeferred_TheyAreAllProcessedOnSpawn()
         {
-            RegisterClientPrefabs();
+            m_SkipAddingPrefabsToClient = true;
+            yield return SpawnClients();
             CatchSpawns();
 
-            // Have to start these before spawning here because spawning sends a NetworkVariableDeltaMessage, too
-            // Depending on timing, if we start this after spawning, we may end up missing the first one.
-            var waiters = WaitForAllClientsToReceive<ClientRpcMessage, NetworkVariableDeltaMessage, NetworkVariableDeltaMessage, ChangeOwnershipMessage>();
-            var coroutines = StartMultiple(waiters);
-
             var serverObject = Object.Instantiate(m_RpcAndNetworkVariablePrefab);
             serverObject.GetComponent<NetworkObject>().NetworkManagerOwner = m_ServerNetworkManager;
             serverObject.GetComponent<NetworkObject>().Spawn();
@@ -679,10 +653,12 @@ namespace Unity.Netcode.RuntimeTests
 
             serverObject.GetComponent<DeferredMessageTestRpcAndNetworkVariableComponent>().SendTestClientRpc();
             serverObject.GetComponent<DeferredMessageTestRpcAndNetworkVariableComponent>().TestNetworkVariable.Value = 1;
+
+            yield return WaitForAllClientsToReceive<ClientRpcMessage, NetworkVariableDeltaMessage>();
+
             serverObject.GetComponent<NetworkObject>().ChangeOwnership(m_ClientNetworkManagers[0].LocalClientId);
 
-            // Should be received in order so we'll wait for the last one.
-            yield return WaitMultiple(coroutines);
+            yield return WaitForAllClientsToReceive<ChangeOwnershipMessage>();
 
             foreach (var client in m_ClientNetworkManagers)
             {
@@ -690,29 +666,49 @@ namespace Unity.Netcode.RuntimeTests
                 Assert.IsTrue(manager.DeferMessageCalled);
                 Assert.IsFalse(manager.ProcessTriggersCalled);
 
-                Assert.AreEqual(4, manager.DeferredMessageCountTotal());
-                Assert.AreEqual(4, manager.DeferredMessageCountForType(IDeferredMessageManager.TriggerType.OnSpawn));
-                Assert.AreEqual(4, manager.DeferredMessageCountForKey(IDeferredMessageManager.TriggerType.OnSpawn, serverObject.GetComponent<NetworkObject>().NetworkObjectId));
+                Assert.AreEqual(3, manager.DeferredMessageCountTotal());
+                Assert.AreEqual(3, manager.DeferredMessageCountForType(IDeferredMessageManager.TriggerType.OnSpawn));
+                Assert.AreEqual(3, manager.DeferredMessageCountForKey(IDeferredMessageManager.TriggerType.OnSpawn, serverObject.GetComponent<NetworkObject>().NetworkObjectId));
                 Assert.AreEqual(0, manager.DeferredMessageCountForType(IDeferredMessageManager.TriggerType.OnAddPrefab));
+                AddPrefabsToClient(client);
             }
+
             ReleaseSpawns();
 
+            // Wait for the clients to spawn the NetworkObjects
+            bool HaveAllClientsSpawned()
+            {
+                foreach (var client in m_ClientNetworkManagers)
+                {
+                    if (!DeferredMessageTestRpcAndNetworkVariableComponent.ClientInstances.Contains(client.LocalClientId))
+                    {
+                        return false;
+                    }
+                }
+                return true;
+            }
+            yield return WaitForConditionOrTimeOut(HaveAllClientsSpawned);
+            yield return new WaitForSeconds(0.1f);
+
+            // Validate the spawned objects
             foreach (var client in m_ClientNetworkManagers)
             {
                 var manager = (TestDeferredMessageManager)client.DeferredMessageManager;
-                Assert.IsTrue(manager.ProcessTriggersCalled);
-                Assert.AreEqual(0, manager.DeferredMessageCountTotal());
+                Assert.IsTrue(manager.ProcessTriggersCalled, "Process triggers were not called!");
+                Assert.AreEqual(0, manager.DeferredMessageCountTotal(), $"Deferred message count ({manager.DeferredMessageCountTotal()}) is not zero!");
 
                 var component = GetComponentForClient<DeferredMessageTestRpcAndNetworkVariableComponent>(client.LocalClientId);
-                Assert.IsTrue(component.ClientRpcCalled);
-                Assert.AreEqual(1, component.TestNetworkVariable.Value);
-                Assert.AreEqual(m_ClientNetworkManagers[0].LocalClientId, component.OwnerClientId);
+                Assert.IsTrue(component.ClientRpcCalled, "Client RPC was not called!");
+                Assert.AreEqual(1, component.TestNetworkVariable.Value, $"Test {nameof(NetworkVariable<int>)} ({component.TestNetworkVariable.Value}) does not equal 1!");
+                Assert.AreEqual(m_ClientNetworkManagers[0].LocalClientId, component.OwnerClientId, $"{component.name} owner id ({component.OwnerClientId}) does not equal first client id ({m_ClientNetworkManagers[0].LocalClientId})");
             }
         }
 
         [UnityTest]
         public IEnumerator WhenMultipleAddPrefabTriggeredMessagesAreDeferred_TheyAreAllProcessedOnAddNetworkPrefab()
         {
+            m_SkipAddingPrefabsToClient = true;
+            yield return SpawnClients();
             var serverObject = Object.Instantiate(m_RpcPrefab);
             serverObject.GetComponent<NetworkObject>().NetworkManagerOwner = m_ServerNetworkManager;
             serverObject.GetComponent<NetworkObject>().Spawn();
@@ -721,7 +717,7 @@ namespace Unity.Netcode.RuntimeTests
             serverObject2.GetComponent<NetworkObject>().NetworkManagerOwner = m_ServerNetworkManager;
             serverObject2.GetComponent<NetworkObject>().Spawn();
 
-            yield return RunMultiple(WaitForAllClientsToReceive<CreateObjectMessage, CreateObjectMessage>());
+            yield return WaitForAllClientsToReceive<CreateObjectMessage, CreateObjectMessage>();
 
             foreach (var client in m_ClientNetworkManagers)
             {
@@ -733,9 +729,23 @@ namespace Unity.Netcode.RuntimeTests
                 Assert.AreEqual(0, manager.DeferredMessageCountForType(IDeferredMessageManager.TriggerType.OnSpawn));
                 Assert.AreEqual(2, manager.DeferredMessageCountForType(IDeferredMessageManager.TriggerType.OnAddPrefab));
                 Assert.AreEqual(2, manager.DeferredMessageCountForKey(IDeferredMessageManager.TriggerType.OnAddPrefab, serverObject.GetComponent<NetworkObject>().GlobalObjectIdHash));
+                AddPrefabsToClient(client);
             }
 
-            RegisterClientPrefabs(false);
+            // Wait for the clients to spawn the NetworkObjects
+            bool HaveAllClientsSpawned()
+            {
+                foreach (var client in m_ClientNetworkManagers)
+                {
+                    if (!DeferredMessageTestRpcComponent.ClientInstances.Contains(client.LocalClientId))
+                    {
+                        return false;
+                    }
+                }
+                return true;
+            }
+            yield return WaitForConditionOrTimeOut(HaveAllClientsSpawned);
+
 
             foreach (var client in m_ClientNetworkManagers)
             {
@@ -769,10 +779,8 @@ namespace Unity.Netcode.RuntimeTests
         [UnityTest]
         public IEnumerator WhenSpawnTriggeredMessagesAreDeferredBeforeThePrefabIsAdded_AddingThePrefabCausesThemToBeProcessed()
         {
-            // Because we're not waiting for the client to receive the spawn before we change the network variable value,
-            // there's only one NetworkVariableDeltaMessage this time.
-            var waiters = WaitForAllClientsToReceive<CreateObjectMessage, ClientRpcMessage, NetworkVariableDeltaMessage, ChangeOwnershipMessage>();
-            var coroutines = StartMultiple(waiters);
+            m_SkipAddingPrefabsToClient = true;
+            yield return SpawnClients();
 
             var serverObject = Object.Instantiate(m_RpcAndNetworkVariablePrefab);
             serverObject.GetComponent<NetworkObject>().NetworkManagerOwner = m_ServerNetworkManager;
@@ -780,10 +788,15 @@ namespace Unity.Netcode.RuntimeTests
 
             serverObject.GetComponent<DeferredMessageTestRpcAndNetworkVariableComponent>().SendTestClientRpc();
             serverObject.GetComponent<DeferredMessageTestRpcAndNetworkVariableComponent>().TestNetworkVariable.Value = 1;
+            // TODO: Remove this if we figure out how to work around the NetworkVariableDeltaMessage.Serialized issue at line 59
+            // Otherwise, we have to wait for at least 1 tick for the NetworkVariableDeltaMessage to be generated before changing ownership
+            yield return WaitForAllClientsToReceive<CreateObjectMessage, ClientRpcMessage, NetworkVariableDeltaMessage>();
+
             serverObject.GetComponent<NetworkObject>().ChangeOwnership(m_ClientNetworkManagers[0].LocalClientId);
 
-            yield return WaitMultiple(coroutines);
+            yield return WaitForAllClientsToReceive<ChangeOwnershipMessage>();
 
+            // Validate messages are deferred and pending
             foreach (var client in m_ClientNetworkManagers)
             {
                 var manager = (TestDeferredMessageManager)client.DeferredMessageManager;
@@ -794,10 +807,26 @@ namespace Unity.Netcode.RuntimeTests
                 Assert.AreEqual(3, manager.DeferredMessageCountForKey(IDeferredMessageManager.TriggerType.OnSpawn, serverObject.GetComponent<NetworkObject>().NetworkObjectId));
                 Assert.AreEqual(1, manager.DeferredMessageCountForType(IDeferredMessageManager.TriggerType.OnAddPrefab));
                 Assert.AreEqual(1, manager.DeferredMessageCountForKey(IDeferredMessageManager.TriggerType.OnAddPrefab, serverObject.GetComponent<NetworkObject>().GlobalObjectIdHash));
+                AddPrefabsToClient(client);
             }
 
-            RegisterClientPrefabs(false);
+            // Wait for the clients to spawn the NetworkObjects
+            bool HaveAllClientsSpawned()
+            {
+                foreach (var client in m_ClientNetworkManagers)
+                {
+                    if (!DeferredMessageTestRpcAndNetworkVariableComponent.ClientInstances.Contains(client.LocalClientId))
+                    {
+                        return false;
+                    }
+                }
+                return true;
+            }
+            yield return WaitForConditionOrTimeOut(HaveAllClientsSpawned);
 
+            yield return new WaitForSeconds(0.1f);
+
+            // Validate the test
             foreach (var client in m_ClientNetworkManagers)
             {
                 var manager = (TestDeferredMessageManager)client.DeferredMessageManager;
@@ -815,7 +844,8 @@ namespace Unity.Netcode.RuntimeTests
         [UnityTest]
         public IEnumerator WhenAMessageIsDeferredForMoreThanTheConfiguredTime_ItIsRemoved([Values(1, 2, 3)] int timeout)
         {
-            RegisterClientPrefabs();
+            m_SkipAddingPrefabsToClient = true;
+            yield return SpawnClients();
             CatchSpawns();
             foreach (var client in m_ClientNetworkManagers)
             {
@@ -869,24 +899,29 @@ namespace Unity.Netcode.RuntimeTests
 
             yield return new WaitForSeconds(timeout + 0.1f);
 
-            Assert.AreEqual(NumberOfClients, purgeCount);
-            foreach (var client in m_ClientNetworkManagers)
+            bool HaveAllClientsPurged()
             {
-                var manager = (TestDeferredMessageManager)client.DeferredMessageManager;
-                Assert.AreEqual(0, manager.DeferredMessageCountTotal());
+                foreach (var client in m_ClientNetworkManagers)
+                {
+                    var manager = (TestDeferredMessageManager)client.DeferredMessageManager;
+                    if (manager.DeferredMessageCountTotal() != 0)
+                    {
+                        return false;
+                    }
+                }
+                return true;
             }
+
+            yield return WaitForConditionOrTimeOut(HaveAllClientsPurged);
+            AssertOnTimeout("Timed out waiting for all clients to purge their deferred messages!");
         }
 
         [UnityTest]
-        [Ignore("This test is unstable on standalones")]
         public IEnumerator WhenMultipleMessagesForTheSameObjectAreDeferredForMoreThanTheConfiguredTime_TheyAreAllRemoved([Values(1, 2, 3)] int timeout)
         {
-            RegisterClientPrefabs();
+            m_SkipAddingPrefabsToClient = true;
+            yield return SpawnClients();
             CatchSpawns();
-            // Have to start these before spawning here because spawning sends a NetworkVariableDeltaMessage, too
-            // Depending on timing, if we start this after spawning, we may end up missing the first one.
-            var waiters = WaitForAllClientsToReceive<ClientRpcMessage, NetworkVariableDeltaMessage, NetworkVariableDeltaMessage, ChangeOwnershipMessage>();
-            var coroutines = StartMultiple(waiters);
 
             foreach (var client in m_ClientNetworkManagers)
             {
@@ -916,7 +951,9 @@ namespace Unity.Netcode.RuntimeTests
             serverObject.GetComponent<DeferredMessageTestRpcAndNetworkVariableComponent>().TestNetworkVariable.Value = 1;
             serverObject.GetComponent<NetworkObject>().ChangeOwnership(m_ClientNetworkManagers[0].LocalClientId);
 
-            yield return WaitMultiple(coroutines);
+            yield return WaitForMessagesReceived(
+                new List<Type> {typeof(ClientRpcMessage), typeof(NetworkVariableDeltaMessage), typeof(ChangeOwnershipMessage),
+                }, m_ClientNetworkManagers.ToList(), ReceiptType.Received);
 
             foreach (var unused in m_ClientNetworkManagers)
             {
@@ -930,38 +967,40 @@ namespace Unity.Netcode.RuntimeTests
                 {
                     ++purgeCount;
                     var elapsed = Time.realtimeSinceStartup - start;
-                    Assert.GreaterOrEqual(elapsed, timeout - 0.05f);
-                    Assert.AreEqual(4, manager.DeferredMessageCountTotal());
-                    Assert.AreEqual(4, manager.DeferredMessageCountForType(IDeferredMessageManager.TriggerType.OnSpawn));
-                    Assert.AreEqual(4, manager.DeferredMessageCountForKey(IDeferredMessageManager.TriggerType.OnSpawn, key));
+                    Assert.GreaterOrEqual(elapsed, timeout - 0.25f);
+                    Assert.AreEqual(3, manager.DeferredMessageCountTotal());
+                    Assert.AreEqual(3, manager.DeferredMessageCountForType(IDeferredMessageManager.TriggerType.OnSpawn));
+                    Assert.AreEqual(3, manager.DeferredMessageCountForKey(IDeferredMessageManager.TriggerType.OnSpawn, key));
                     Assert.AreEqual(serverObject.GetComponent<NetworkObject>().NetworkObjectId, key);
                 };
                 var manager = (TestDeferredMessageManager)client.DeferredMessageManager;
                 manager.OnBeforePurge = beforePurge;
             }
 
-            yield return new WaitForSeconds(timeout + 0.1f);
-
-            Assert.AreEqual(NumberOfClients, purgeCount);
-            foreach (var client in m_ClientNetworkManagers)
+            bool HaveAllClientsPurged()
             {
-                var manager = (TestDeferredMessageManager)client.DeferredMessageManager;
-                Assert.AreEqual(0, manager.DeferredMessageCountTotal());
+                foreach (var client in m_ClientNetworkManagers)
+                {
+                    var manager = (TestDeferredMessageManager)client.DeferredMessageManager;
+                    if (manager.DeferredMessageCountTotal() != 0)
+                    {
+                        return false;
+                    }
+                }
+                return true;
             }
+
+            yield return WaitForConditionOrTimeOut(HaveAllClientsPurged);
+            AssertOnTimeout("Timed out waiting for all clients to purge their deferred messages!");
         }
 
         [UnityTest]
         public IEnumerator WhenMultipleMessagesForDifferentObjectsAreDeferredForMoreThanTheConfiguredTime_TheyAreAllRemoved([Values(1, 2, 3)] int timeout)
         {
-            RegisterClientPrefabs();
+            m_SkipAddingPrefabsToClient = true;
+            yield return SpawnClients();
             CatchSpawns();
 
-            // Have to start these before spawning here because spawning sends a NetworkVariableDeltaMessage, too
-            // Depending on timing, if we start this after spawning, we may end up missing the first one.
-            var waiters = WaitForAllClientsToReceive<ClientRpcMessage, NetworkVariableDeltaMessage, NetworkVariableDeltaMessage, ChangeOwnershipMessage>();
-            waiters.AddRange(WaitForAllClientsToReceive<ClientRpcMessage, NetworkVariableDeltaMessage, NetworkVariableDeltaMessage, ChangeOwnershipMessage>());
-            var coroutines = StartMultiple(waiters);
-
             foreach (var client in m_ClientNetworkManagers)
             {
                 client.NetworkConfig.SpawnTimeout = timeout;
@@ -999,10 +1038,13 @@ namespace Unity.Netcode.RuntimeTests
             serverObject2.GetComponent<DeferredMessageTestRpcAndNetworkVariableComponent>().TestNetworkVariable.Value = 1;
             serverObject2.GetComponent<NetworkObject>().ChangeOwnership(m_ClientNetworkManagers[0].LocalClientId);
 
-            yield return WaitMultiple(coroutines);
+            yield return WaitForMessagesReceived(
+            new List<Type> {typeof(ClientRpcMessage), typeof(NetworkVariableDeltaMessage), typeof(ChangeOwnershipMessage),typeof(ClientRpcMessage), typeof(NetworkVariableDeltaMessage), typeof(ChangeOwnershipMessage),
+            }, m_ClientNetworkManagers.ToList(), ReceiptType.Received);
 
             foreach (var unused in m_ClientNetworkManagers)
             {
+
                 LogAssert.Expect(LogType.Warning, $"[Netcode] Deferred messages were received for a trigger of type {IDeferredMessageManager.TriggerType.OnSpawn} with key {serverObject.GetComponent<NetworkObject>().NetworkObjectId}, but that trigger was not received within within {timeout} second(s).");
                 LogAssert.Expect(LogType.Warning, $"[Netcode] Deferred messages were received for a trigger of type {IDeferredMessageManager.TriggerType.OnSpawn} with key {serverObject2.GetComponent<NetworkObject>().NetworkObjectId}, but that trigger was not received within within {timeout} second(s).");
             }
@@ -1010,24 +1052,27 @@ namespace Unity.Netcode.RuntimeTests
             int purgeCount = 0;
             foreach (var client in m_ClientNetworkManagers)
             {
-                var remainingMessagesTotalThisClient = 8;
+                var remainingMessagesTotalThisClient = 6;
                 TestDeferredMessageManager.BeforePurgeDelegate beforePurge = (manager, key) =>
                 {
                     ++purgeCount;
                     var elapsed = Time.realtimeSinceStartup - start;
-                    Assert.GreaterOrEqual(elapsed, timeout - 0.05f);
+                    Assert.GreaterOrEqual(elapsed, timeout - 0.25f);
                     Assert.AreEqual(remainingMessagesTotalThisClient, manager.DeferredMessageCountTotal());
                     Assert.AreEqual(remainingMessagesTotalThisClient, manager.DeferredMessageCountForType(IDeferredMessageManager.TriggerType.OnSpawn));
-                    Assert.AreEqual(4, manager.DeferredMessageCountForKey(IDeferredMessageManager.TriggerType.OnSpawn, key));
-                    remainingMessagesTotalThisClient -= 4;
+                    Assert.AreEqual(3, manager.DeferredMessageCountForKey(IDeferredMessageManager.TriggerType.OnSpawn, key));
+                    remainingMessagesTotalThisClient -= 3;
                 };
                 var manager = (TestDeferredMessageManager)client.DeferredMessageManager;
                 manager.OnBeforePurge = beforePurge;
             }
 
             yield return new WaitForSeconds(timeout + 0.1f);
-
-            Assert.AreEqual(NumberOfClients * 2, purgeCount);
+            foreach (var client in m_ClientNetworkManagers)
+            {
+                AddPrefabsToClient(client);
+            }
+            Assert.AreEqual(m_NumberOfClientsToLateJoin * 2, purgeCount);
             foreach (var client in m_ClientNetworkManagers)
             {
                 var manager = (TestDeferredMessageManager)client.DeferredMessageManager;
@@ -1038,7 +1083,8 @@ namespace Unity.Netcode.RuntimeTests
         [UnityTest]
         public IEnumerator WhenADeferredMessageIsRemoved_OtherMessagesForSameObjectAreRemoved([Values(1, 2, 3)] int timeout)
         {
-            RegisterClientPrefabs();
+            m_SkipAddingPrefabsToClient = true;
+            yield return SpawnClients();
             CatchSpawns();
             foreach (var client in m_ClientNetworkManagers)
             {
@@ -1066,7 +1112,7 @@ namespace Unity.Netcode.RuntimeTests
 
             serverObject.GetComponent<NetworkObject>().ChangeOwnership(m_ClientNetworkManagers[0].LocalClientId);
 
-            yield return RunMultiple(WaitForAllClientsToReceive<ChangeOwnershipMessage>());
+            yield return WaitForAllClientsToReceive<ChangeOwnershipMessage>();
 
             yield return new WaitForSeconds(timeout - 0.5f);
 
@@ -1079,7 +1125,7 @@ namespace Unity.Netcode.RuntimeTests
             }
 
             serverObject.GetComponent<NetworkObject>().ChangeOwnership(m_ServerNetworkManager.LocalClientId);
-            yield return RunMultiple(WaitForAllClientsToReceive<ChangeOwnershipMessage>());
+            yield return WaitForAllClientsToReceive<ChangeOwnershipMessage>();
 
             foreach (var client in m_ClientNetworkManagers)
             {
@@ -1111,9 +1157,14 @@ namespace Unity.Netcode.RuntimeTests
                 manager.OnBeforePurge = beforePurge;
             }
 
+            foreach (var client in m_ClientNetworkManagers)
+            {
+                AddPrefabsToClient(client);
+            }
+
             yield return new WaitForSeconds(0.6f);
 
-            Assert.AreEqual(NumberOfClients, purgeCount);
+            Assert.AreEqual(m_NumberOfClientsToLateJoin, purgeCount);
             foreach (var client in m_ClientNetworkManagers)
             {
                 var manager = (TestDeferredMessageManager)client.DeferredMessageManager;
@@ -1124,7 +1175,8 @@ namespace Unity.Netcode.RuntimeTests
         [UnityTest]
         public IEnumerator WhenADeferredMessageIsRemoved_OtherMessagesForDifferentObjectsAreNotRemoved([Values(1, 2, 3)] int timeout)
         {
-            RegisterClientPrefabs();
+            m_SkipAddingPrefabsToClient = true;
+            yield return SpawnClients();
             CatchSpawns();
             foreach (var client in m_ClientNetworkManagers)
             {
@@ -1155,7 +1207,7 @@ namespace Unity.Netcode.RuntimeTests
 
             serverObject.GetComponent<NetworkObject>().ChangeOwnership(m_ClientNetworkManagers[0].LocalClientId);
 
-            yield return RunMultiple(WaitForAllClientsToReceive<ChangeOwnershipMessage>());
+            yield return WaitForAllClientsToReceive<ChangeOwnershipMessage>();
 
             yield return new WaitForSeconds(timeout - 0.5f);
 
@@ -1169,7 +1221,7 @@ namespace Unity.Netcode.RuntimeTests
             }
 
             serverObject2.GetComponent<NetworkObject>().ChangeOwnership(m_ServerNetworkManager.LocalClientId);
-            yield return RunMultiple(WaitForAllClientsToReceive<ChangeOwnershipMessage>());
+            yield return WaitForAllClientsToReceive<ChangeOwnershipMessage>();
 
             foreach (var client in m_ClientNetworkManagers)
             {
@@ -1205,9 +1257,14 @@ namespace Unity.Netcode.RuntimeTests
                 manager.OnBeforePurge = beforePurge;
             }
 
+            foreach (var client in m_ClientNetworkManagers)
+            {
+                AddPrefabsToClient(client);
+            }
+
             yield return new WaitForSeconds(0.6f);
 
-            Assert.AreEqual(NumberOfClients, purgeCount);
+            Assert.AreEqual(m_NumberOfClientsToLateJoin, purgeCount);
             foreach (var client in m_ClientNetworkManagers)
             {
                 var manager = (TestDeferredMessageManager)client.DeferredMessageManager;

Tests/Runtime/DisconnectTests.cs

@@ -60,5 +60,53 @@ namespace Unity.Netcode.RuntimeTests
         {
             m_ClientDisconnected = true;
         }
+
+        [UnityTest]
+        public IEnumerator ClientDisconnectPlayerObjectCleanup()
+        {
+            // create server and client instances
+            NetcodeIntegrationTestHelpers.Create(1, out NetworkManager server, out NetworkManager[] clients);
+
+            // create prefab
+            var gameObject = new GameObject("PlayerObject");
+            var networkObject = gameObject.AddComponent<NetworkObject>();
+            networkObject.DontDestroyWithOwner = true;
+            NetcodeIntegrationTestHelpers.MakeNetworkObjectTestPrefab(networkObject);
+
+            server.NetworkConfig.PlayerPrefab = gameObject;
+
+            for (int i = 0; i < clients.Length; i++)
+            {
+                clients[i].NetworkConfig.PlayerPrefab = gameObject;
+            }
+
+            // start server and connect clients
+            NetcodeIntegrationTestHelpers.Start(false, server, clients);
+
+            // wait for connection on client side
+            yield return NetcodeIntegrationTestHelpers.WaitForClientsConnected(clients);
+
+            // wait for connection on server side
+            yield return NetcodeIntegrationTestHelpers.WaitForClientConnectedToServer(server);
+
+            // disconnect the remote client
+            m_ClientDisconnected = false;
+
+            server.OnClientDisconnectCallback += OnClientDisconnectCallback;
+
+            var serverSideClientPlayer = server.ConnectedClients[clients[0].LocalClientId].PlayerObject;
+
+            // Stopping the client is the same as the client disconnecting
+            NetcodeIntegrationTestHelpers.StopOneClient(clients[0]);
+
+            var timeoutHelper = new TimeoutHelper();
+            yield return NetcodeIntegrationTest.WaitForConditionOrTimeOut(() => m_ClientDisconnected, timeoutHelper);
+
+            // ensure the object was destroyed
+            Assert.True(serverSideClientPlayer.IsOwnedByServer, $"The client's player object's ownership was not transferred back to the server!");
+
+            // cleanup
+            NetcodeIntegrationTestHelpers.Destroy();
+        }
     }
 }

Tests/Runtime/ListChangedTest.cs

@@ -0,0 +1,82 @@
+using System.Collections;
+using UnityEngine;
+using UnityEngine.TestTools;
+using Unity.Netcode.TestHelpers.Runtime;
+
+namespace Unity.Netcode.RuntimeTests
+{
+    public class NetworkListChangedTestComponent : NetworkBehaviour
+    {
+
+    }
+
+    public class ListChangedObject : NetworkBehaviour
+    {
+        public int ExpectedPreviousValue = 0;
+        public int ExpectedValue = 0;
+        public bool AddDone = false;
+
+        public NetworkList<int> MyNetworkList = new NetworkList<int>();
+
+        public override void OnNetworkSpawn()
+        {
+            MyNetworkList.OnListChanged += Changed;
+            base.OnNetworkSpawn();
+        }
+
+        public void Changed(NetworkListEvent<int> listEvent)
+        {
+            if (listEvent.Type == NetworkListEvent<int>.EventType.Value)
+            {
+                if (listEvent.PreviousValue != ExpectedPreviousValue)
+                {
+                    Debug.Log($"Expected previous value mismatch {listEvent.PreviousValue} versus {ExpectedPreviousValue}");
+                    Debug.Assert(listEvent.PreviousValue == ExpectedPreviousValue);
+                }
+
+                if (listEvent.Value != ExpectedValue)
+                {
+                    Debug.Log($"Expected value mismatch {listEvent.Value} versus {ExpectedValue}");
+                    Debug.Assert(listEvent.Value == ExpectedValue);
+                }
+
+                AddDone = true;
+            }
+        }
+    }
+
+    public class NetworkListChangedTests : NetcodeIntegrationTest
+    {
+        protected override int NumberOfClients => 2;
+
+        private ulong m_ClientId0;
+        private GameObject m_PrefabToSpawn;
+
+        private NetworkObject m_NetSpawnedObject1;
+
+        protected override void OnServerAndClientsCreated()
+        {
+            m_PrefabToSpawn = CreateNetworkObjectPrefab("ListChangedObject");
+            m_PrefabToSpawn.AddComponent<ListChangedObject>();
+        }
+
+        [UnityTest]
+        public IEnumerator NetworkListChangedTest()
+        {
+            m_ClientId0 = m_ClientNetworkManagers[0].LocalClientId;
+
+            // create 3 objects
+            var spawnedObject1 = SpawnObject(m_PrefabToSpawn, m_ServerNetworkManager);
+            m_NetSpawnedObject1 = spawnedObject1.GetComponent<NetworkObject>();
+
+            m_NetSpawnedObject1.GetComponent<ListChangedObject>().MyNetworkList.Add(42);
+            m_NetSpawnedObject1.GetComponent<ListChangedObject>().ExpectedPreviousValue = 42;
+            m_NetSpawnedObject1.GetComponent<ListChangedObject>().ExpectedValue = 44;
+            m_NetSpawnedObject1.GetComponent<ListChangedObject>().MyNetworkList[0] = 44;
+
+            Debug.Assert(m_NetSpawnedObject1.GetComponent<ListChangedObject>().AddDone);
+
+            return null;
+        }
+    }
+}

Tests/Runtime/ListChangedTest.cs.meta

@@ -0,0 +1,11 @@
+fileFormatVersion: 2
+guid: b269e2a059f814075a737691bc02afa4
+MonoImporter:
+  externalObjects: {}
+  serializedVersion: 2
+  defaultReferences: []
+  executionOrder: 0
+  icon: {instanceID: 0}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: 

Tests/Runtime/Metrics/ConnectionMetricsTests.cs

@@ -2,7 +2,6 @@
 #if MULTIPLAYER_TOOLS_1_0_0_PRE_7
 
 using System.Collections;
-using System.Collections.Generic;
 using NUnit.Framework;
 using Unity.Multiplayer.Tools.MetricTypes;
 using Unity.Netcode.TestHelpers.Runtime;

Tests/Runtime/Metrics/MetricsDispatchTests.cs

@@ -5,7 +5,6 @@ using NUnit.Framework;
 using Unity.Multiplayer.Tools.NetStats;
 using UnityEngine.TestTools;
 using Unity.Netcode.TestHelpers.Runtime;
-using Unity.Netcode.TestHelpers.Runtime.Metrics;
 
 namespace Unity.Netcode.RuntimeTests.Metrics
 {

Tests/Runtime/Metrics/NetworkVariableMetricsTests.cs

@@ -25,10 +25,17 @@ namespace Unity.Netcode.RuntimeTests.Metrics
 
             var metricValues = waitForMetricValues.AssertMetricValuesHaveBeenFound();
 
-            var networkVariableDeltaSent = metricValues.First();
-            Assert.AreEqual(nameof(NetworkVariableComponent.MyNetworkVariable), networkVariableDeltaSent.Name);
-            Assert.AreEqual(Server.LocalClientId, networkVariableDeltaSent.Connection.Id);
-            Assert.AreNotEqual(0, networkVariableDeltaSent.BytesCount);
+            bool found = false;
+            foreach (var networkVariableDeltaSent in metricValues)
+            {
+                if (nameof(NetworkVariableComponent.MyNetworkVariable) == networkVariableDeltaSent.Name &&
+                    Client.LocalClientId == networkVariableDeltaSent.Connection.Id &&
+                    0 != networkVariableDeltaSent.BytesCount)
+                {
+                    found = true;
+                }
+            }
+            Assert.IsTrue(found);
         }
 
         [UnityTest]

Tests/Runtime/Metrics/OwnershipChangeMetricsTests.cs

@@ -1,5 +1,4 @@
 #if MULTIPLAYER_TOOLS
-using System;
 using System.Collections;
 using System.Linq;
 using NUnit.Framework;
@@ -36,7 +35,7 @@ namespace Unity.Netcode.RuntimeTests.Metrics
         private NetworkObject SpawnNetworkObject()
         {
             // Spawn another network object so we can hide multiple.
-            var gameObject = UnityEngine.Object.Instantiate(m_NewNetworkPrefab); // new GameObject(NewNetworkObjectName);
+            var gameObject = Object.Instantiate(m_NewNetworkPrefab); // new GameObject(NewNetworkObjectName);
             var networkObject = gameObject.GetComponent<NetworkObject>();
             networkObject.NetworkManagerOwner = Server;
             networkObject.Spawn();
@@ -62,6 +61,13 @@ namespace Unity.Netcode.RuntimeTests.Metrics
             var ownershipChangeSent = metricValues.First();
             Assert.AreEqual(networkObject.NetworkObjectId, ownershipChangeSent.NetworkId.NetworkId);
             Assert.AreEqual(Server.LocalClientId, ownershipChangeSent.Connection.Id);
+            Assert.AreEqual(0, ownershipChangeSent.BytesCount);
+
+            // The first metric is to the server(self), so its size is now correctly reported as 0.
+            // Let's check the last one instead, to have a valid value
+            ownershipChangeSent = metricValues.Last();
+            Assert.AreEqual(networkObject.NetworkObjectId, ownershipChangeSent.NetworkId.NetworkId);
+            Assert.AreEqual(Client.LocalClientId, ownershipChangeSent.Connection.Id);
             Assert.AreEqual(FastBufferWriter.GetWriteSize<ChangeOwnershipMessage>() + k_MessageHeaderSize, ownershipChangeSent.BytesCount);
         }
 

Tests/Runtime/Metrics/PacketLossMetricsTests.cs

@@ -1,7 +1,6 @@
 #if MULTIPLAYER_TOOLS
 #if MULTIPLAYER_TOOLS_1_0_0_PRE_7
 
-using System;
 using System.Collections;
 using NUnit.Framework;
 using Unity.Collections;
@@ -9,7 +8,9 @@ using Unity.Multiplayer.Tools.MetricTypes;
 using Unity.Netcode.TestHelpers.Runtime;
 using Unity.Netcode.TestHelpers.Runtime.Metrics;
 using Unity.Netcode.Transports.UTP;
-using UnityEngine;
+#if UTP_TRANSPORT_2_0_ABOVE
+using Unity.Networking.Transport.Utilities;
+#endif
 using UnityEngine.TestTools;
 
 namespace Unity.Netcode.RuntimeTests.Metrics
@@ -18,16 +19,25 @@ namespace Unity.Netcode.RuntimeTests.Metrics
     {
         protected override int NumberOfClients => 1;
         private readonly int m_PacketLossRate = 25;
-        private readonly int m_PacketLossRangeDelta = 5;
+        private readonly int m_PacketLossRangeDelta = 3;
+        private readonly int m_MessageSize = 200;
 
         public PacketLossMetricsTests()
             : base(HostOrServer.Server)
-        {}
+        { }
 
         protected override void OnServerAndClientsCreated()
         {
             var clientTransport = (UnityTransport)m_ClientNetworkManagers[0].NetworkConfig.NetworkTransport;
+#if !UTP_TRANSPORT_2_0_ABOVE
             clientTransport.SetDebugSimulatorParameters(0, 0, m_PacketLossRate);
+#endif
+
+            // Determined through trial and error. With both UTP 1.2 and 2.0, this random seed
+            // results in an effective packet loss percentage between 22% and 28%. Future UTP
+            // updates may change the RNG call patterns and cause this test to fail, in which
+            // case the value should be modified again.
+            clientTransport.DebugSimulatorRandomSeed = 4;
 
             base.OnServerAndClientsCreated();
         }
@@ -41,11 +51,9 @@ namespace Unity.Netcode.RuntimeTests.Metrics
 
             for (int i = 0; i < 1000; ++i)
             {
-                using (var writer = new FastBufferWriter(sizeof(byte), Allocator.Persistent))
-                {
-                    writer.WriteByteSafe(42);
-                    m_ServerNetworkManager.CustomMessagingManager.SendNamedMessage("Test", m_ServerNetworkManager.ConnectedClientsIds, writer);
-                }
+                using var writer = new FastBufferWriter(m_MessageSize, Allocator.Persistent);
+                writer.WriteBytesSafe(new byte[m_MessageSize]);
+                m_ServerNetworkManager.CustomMessagingManager.SendNamedMessage("Test", m_ServerNetworkManager.ConnectedClientsIds, writer);
             }
 
             yield return waitForPacketLossMetric.WaitForMetricsReceived();
@@ -57,20 +65,26 @@ namespace Unity.Netcode.RuntimeTests.Metrics
         [UnityTest]
         public IEnumerator TrackPacketLossAsClient()
         {
-            double packetLossRateMinRange = (m_PacketLossRate-m_PacketLossRangeDelta) / 100d;
+            double packetLossRateMinRange = (m_PacketLossRate - m_PacketLossRangeDelta) / 100d;
             double packetLossRateMaxrange = (m_PacketLossRate + m_PacketLossRangeDelta) / 100d;
             var clientNetworkManager = m_ClientNetworkManagers[0];
+
+#if UTP_TRANSPORT_2_0_ABOVE
+            var clientTransport = (UnityTransport)clientNetworkManager.NetworkConfig.NetworkTransport;
+            clientTransport.NetworkDriver.CurrentSettings.TryGet<SimulatorUtility.Parameters>(out var parameters);
+            parameters.PacketDropPercentage = m_PacketLossRate;
+            clientTransport.NetworkDriver.ModifySimulatorStageParameters(parameters);
+#endif
+
             var waitForPacketLossMetric = new WaitForGaugeMetricValues((clientNetworkManager.NetworkMetrics as NetworkMetrics).Dispatcher,
                 NetworkMetricTypes.PacketLoss,
                 metric => packetLossRateMinRange <= metric && metric <= packetLossRateMaxrange);
 
             for (int i = 0; i < 1000; ++i)
             {
-                using (var writer = new FastBufferWriter(sizeof(byte), Allocator.Persistent))
-                {
-                    writer.WriteByteSafe(42);
-                    m_ServerNetworkManager.CustomMessagingManager.SendNamedMessage("Test", m_ServerNetworkManager.ConnectedClientsIds, writer);
-                }
+                using var writer = new FastBufferWriter(m_MessageSize, Allocator.Persistent);
+                writer.WriteBytesSafe(new byte[m_MessageSize]);
+                m_ServerNetworkManager.CustomMessagingManager.SendNamedMessage("Test", m_ServerNetworkManager.ConnectedClientsIds, writer);
             }
 
             yield return waitForPacketLossMetric.WaitForMetricsReceived();

Tests/Runtime/Metrics/PacketMetricsTests.cs

@@ -5,7 +5,6 @@ using NUnit.Framework;
 using Unity.Collections;
 using Unity.Multiplayer.Tools.MetricTypes;
 using UnityEngine.TestTools;
-using Unity.Netcode.TestHelpers.Runtime;
 using Unity.Netcode.TestHelpers.Runtime.Metrics;
 
 namespace Unity.Netcode.RuntimeTests.Metrics

Tests/Runtime/Metrics/RpcMetricsTests.cs

@@ -2,13 +2,14 @@
 using System.Collections;
 using System.Linq;
 using NUnit.Framework;
+using Unity.Collections;
 using Unity.Multiplayer.Tools.MetricTypes;
 using UnityEngine.TestTools;
 using Unity.Netcode.TestHelpers.Runtime.Metrics;
 
 namespace Unity.Netcode.RuntimeTests.Metrics
 {
-    internal class RpcMetricsTests : SingleClientMetricTestBase
+    internal class RpcMetricsTests : DualClientMetricTestBase
     {
         protected override void OnCreatePlayerPrefab()
         {
@@ -17,30 +18,79 @@ namespace Unity.Netcode.RuntimeTests.Metrics
         }
 
         [UnityTest]
-        public IEnumerator TrackRpcSentMetricOnServer()
+        public IEnumerator TrackRpcSentMetricOnServerToOnlyOneClientWithArray()
         {
             var waitForMetricValues = new WaitForEventMetricValues<RpcEvent>(ServerMetrics.Dispatcher, NetworkMetricTypes.RpcSent);
 
-            m_PlayerNetworkObjects[m_ServerNetworkManager.LocalClientId][Client.LocalClientId].GetComponent<RpcTestComponent>().MyClientRpc();
+            m_PlayerNetworkObjects[m_ServerNetworkManager.LocalClientId][FirstClient.LocalClientId].GetComponent<RpcTestComponent>().MyClientRpc(new ClientRpcParams
+            {
+                Send = new ClientRpcSendParams
+                {
+                    TargetClientIds = new[] { FirstClient.LocalClientId }
+                }
+            });
 
             yield return waitForMetricValues.WaitForMetricsReceived();
 
             var serverRpcSentValues = waitForMetricValues.AssertMetricValuesHaveBeenFound();
-            Assert.AreEqual(2, serverRpcSentValues.Count); // Server will receive this, since it's host
+            Assert.AreEqual(1, serverRpcSentValues.Count);
+
+            Assert.That(serverRpcSentValues, Has.All.Matches<RpcEvent>(x => x.Name == nameof(RpcTestComponent.MyClientRpc)));
+            Assert.That(serverRpcSentValues, Has.All.Matches<RpcEvent>(x => x.NetworkBehaviourName == nameof(RpcTestComponent)));
+            Assert.That(serverRpcSentValues, Has.All.Matches<RpcEvent>(x => x.BytesCount != 0));
+            Assert.AreEqual(FirstClient.LocalClientId, serverRpcSentValues.First().Connection.Id);
+        }
+
+        [UnityTest]
+        public IEnumerator TrackRpcSentMetricOnServerToOnlyOneClientWithNativeArray()
+        {
+            var waitForMetricValues = new WaitForEventMetricValues<RpcEvent>(ServerMetrics.Dispatcher, NetworkMetricTypes.RpcSent);
+
+            m_PlayerNetworkObjects[m_ServerNetworkManager.LocalClientId][FirstClient.LocalClientId].GetComponent<RpcTestComponent>().MyClientRpc(new ClientRpcParams
+            {
+                Send = new ClientRpcSendParams
+                {
+                    TargetClientIdsNativeArray = new NativeArray<ulong>(new[] { FirstClient.LocalClientId }, Allocator.Temp)
+                }
+            });
+
+            yield return waitForMetricValues.WaitForMetricsReceived();
+
+            var serverRpcSentValues = waitForMetricValues.AssertMetricValuesHaveBeenFound();
+            Assert.AreEqual(1, serverRpcSentValues.Count);
+
+            Assert.That(serverRpcSentValues, Has.All.Matches<RpcEvent>(x => x.Name == nameof(RpcTestComponent.MyClientRpc)));
+            Assert.That(serverRpcSentValues, Has.All.Matches<RpcEvent>(x => x.NetworkBehaviourName == nameof(RpcTestComponent)));
+            Assert.That(serverRpcSentValues, Has.All.Matches<RpcEvent>(x => x.BytesCount != 0));
+            Assert.AreEqual(FirstClient.LocalClientId, serverRpcSentValues.First().Connection.Id);
+        }
+
+        [UnityTest]
+        public IEnumerator TrackRpcSentMetricOnServerToAllClients()
+        {
+            var waitForMetricValues = new WaitForEventMetricValues<RpcEvent>(ServerMetrics.Dispatcher, NetworkMetricTypes.RpcSent);
+
+            m_PlayerNetworkObjects[m_ServerNetworkManager.LocalClientId][FirstClient.LocalClientId].GetComponent<RpcTestComponent>().MyClientRpc();
+
+            yield return waitForMetricValues.WaitForMetricsReceived();
+
+            var serverRpcSentValues = waitForMetricValues.AssertMetricValuesHaveBeenFound();
+            Assert.AreEqual(3, serverRpcSentValues.Count); // Server will receive this, since it's host
 
             Assert.That(serverRpcSentValues, Has.All.Matches<RpcEvent>(x => x.Name == nameof(RpcTestComponent.MyClientRpc)));
             Assert.That(serverRpcSentValues, Has.All.Matches<RpcEvent>(x => x.NetworkBehaviourName == nameof(RpcTestComponent)));
             Assert.That(serverRpcSentValues, Has.All.Matches<RpcEvent>(x => x.BytesCount != 0));
             Assert.Contains(Server.LocalClientId, serverRpcSentValues.Select(x => x.Connection.Id).ToArray());
-            Assert.Contains(Client.LocalClientId, serverRpcSentValues.Select(x => x.Connection.Id).ToArray());
+            Assert.Contains(FirstClient.LocalClientId, serverRpcSentValues.Select(x => x.Connection.Id).ToArray());
+            Assert.Contains(SecondClient.LocalClientId, serverRpcSentValues.Select(x => x.Connection.Id).ToArray());
         }
 
         [UnityTest]
         public IEnumerator TrackRpcSentMetricOnClient()
         {
-            var waitForClientMetricsValues = new WaitForEventMetricValues<RpcEvent>(ClientMetrics.Dispatcher, NetworkMetricTypes.RpcSent);
+            var waitForClientMetricsValues = new WaitForEventMetricValues<RpcEvent>(FirstClientMetrics.Dispatcher, NetworkMetricTypes.RpcSent);
 
-            m_PlayerNetworkObjects[Client.LocalClientId][Client.LocalClientId].GetComponent<RpcTestComponent>().MyServerRpc();
+            m_PlayerNetworkObjects[FirstClient.LocalClientId][FirstClient.LocalClientId].GetComponent<RpcTestComponent>().MyServerRpc();
 
             yield return waitForClientMetricsValues.WaitForMetricsReceived();
 
@@ -58,7 +108,7 @@ namespace Unity.Netcode.RuntimeTests.Metrics
         public IEnumerator TrackRpcReceivedMetricOnServer()
         {
             var waitForServerMetricsValues = new WaitForEventMetricValues<RpcEvent>(ServerMetrics.Dispatcher, NetworkMetricTypes.RpcReceived);
-            m_PlayerNetworkObjects[Client.LocalClientId][Client.LocalClientId].GetComponent<RpcTestComponent>().MyServerRpc();
+            m_PlayerNetworkObjects[FirstClient.LocalClientId][FirstClient.LocalClientId].GetComponent<RpcTestComponent>().MyServerRpc();
 
             yield return waitForServerMetricsValues.WaitForMetricsReceived();
 
@@ -66,7 +116,7 @@ namespace Unity.Netcode.RuntimeTests.Metrics
             Assert.AreEqual(1, serverRpcReceivedValues.Count);
 
             var rpcReceived = serverRpcReceivedValues.First();
-            Assert.AreEqual(Client.LocalClientId, rpcReceived.Connection.Id);
+            Assert.AreEqual(FirstClient.LocalClientId, rpcReceived.Connection.Id);
             Assert.AreEqual(nameof(RpcTestComponent.MyServerRpc), rpcReceived.Name);
             Assert.AreEqual(nameof(RpcTestComponent), rpcReceived.NetworkBehaviourName);
             Assert.AreNotEqual(0, rpcReceived.BytesCount);
@@ -75,9 +125,9 @@ namespace Unity.Netcode.RuntimeTests.Metrics
         [UnityTest]
         public IEnumerator TrackRpcReceivedMetricOnClient()
         {
-            var waitForClientMetricsValues = new WaitForEventMetricValues<RpcEvent>(ClientMetrics.Dispatcher, NetworkMetricTypes.RpcReceived);
+            var waitForClientMetricsValues = new WaitForEventMetricValues<RpcEvent>(FirstClientMetrics.Dispatcher, NetworkMetricTypes.RpcReceived);
 
-            m_PlayerNetworkObjects[m_ServerNetworkManager.LocalClientId][Client.LocalClientId].GetComponent<RpcTestComponent>().MyClientRpc();
+            m_PlayerNetworkObjects[m_ServerNetworkManager.LocalClientId][FirstClient.LocalClientId].GetComponent<RpcTestComponent>().MyClientRpc();
 
             yield return waitForClientMetricsValues.WaitForMetricsReceived();
 

Tests/Runtime/Metrics/TransportBytesMetricsTests.cs

@@ -1,7 +1,6 @@
 #if MULTIPLAYER_TOOLS
 using System;
 using System.Collections;
-using System.IO;
 using NUnit.Framework;
 using Unity.Collections;
 using Unity.Multiplayer.Tools.MetricTypes;
@@ -15,7 +14,7 @@ namespace Unity.Netcode.RuntimeTests.Metrics
     {
         // Header is dynamically sized due to packing, will be 2 bytes for all test messages.
         private const int k_MessageHeaderSize = 2;
-        static readonly long MessageOverhead = 8 + FastBufferWriter.GetWriteSize<BatchHeader>() + k_MessageHeaderSize;
+        private static readonly long k_MessageOverhead = 8 + FastBufferWriter.GetWriteSize<BatchHeader>() + k_MessageHeaderSize;
 
         [UnityTest]
         public IEnumerator TrackTotalNumberOfBytesSent()
@@ -42,7 +41,7 @@ namespace Unity.Netcode.RuntimeTests.Metrics
             }
 
             Assert.True(observer.Found);
-            Assert.AreEqual(FastBufferWriter.GetWriteSize(messageName) + MessageOverhead, observer.Value);
+            Assert.AreEqual(FastBufferWriter.GetWriteSize(messageName) + k_MessageOverhead, observer.Value);
         }
 
         [UnityTest]
@@ -72,7 +71,7 @@ namespace Unity.Netcode.RuntimeTests.Metrics
             }
 
             Assert.True(observer.Found);
-            Assert.AreEqual(FastBufferWriter.GetWriteSize(messageName) + MessageOverhead, observer.Value);
+            Assert.AreEqual(FastBufferWriter.GetWriteSize(messageName) + k_MessageOverhead, observer.Value);
         }
 
         private class TotalBytesObserver : IMetricObserver

Tests/Runtime/NetworkAnimator.meta

@@ -1,8 +0,0 @@
-fileFormatVersion: 2
-guid: 3acde7838205d4b09ae3a035554c51c5
-folderAsset: yes
-DefaultImporter:
-  externalObjects: {}
-  userData: 
-  assetBundleName: 
-  assetBundleVariant: 

Tests/Runtime/NetworkAnimator/NetworkAnimatorTests.cs

@@ -1,239 +0,0 @@
-#if COM_UNITY_MODULES_ANIMATION
-using System.Collections;
-using System.Collections.Generic;
-using NUnit.Framework;
-using Unity.Netcode.Components;
-using UnityEngine;
-using UnityEngine.TestTools;
-using Unity.Netcode.TestHelpers.Runtime;
-
-namespace Unity.Netcode.RuntimeTests
-{
-    [TestFixture(HostOrServer.Host)]
-    [TestFixture(HostOrServer.Server)]
-    public class NetworkAnimatorTests : NetcodeIntegrationTest
-    {
-        protected override int NumberOfClients => 1;
-
-        private GameObject m_PlayerOnServer;
-        private GameObject m_PlayerOnClient;
-
-        private Animator m_PlayerOnServerAnimator;
-        private Animator m_PlayerOnClientAnimator;
-
-        public NetworkAnimatorTests(HostOrServer hostOrServer) : base(hostOrServer) { }
-
-        protected override void OnCreatePlayerPrefab()
-        {
-            // ideally, we would build up the AnimatorController entirely in code and not need an asset,
-            //  but after some attempts this doesn't seem readily doable.  Instead, we load a controller
-            var controller = Resources.Load("TestAnimatorController") as RuntimeAnimatorController;
-            var animator = m_PlayerPrefab.AddComponent<Animator>();
-            animator.runtimeAnimatorController = controller;
-
-            var networkAnimator = m_PlayerPrefab.AddComponent<NetworkAnimator>();
-            networkAnimator.Animator = animator;
-        }
-
-        protected override IEnumerator OnServerAndClientsConnected()
-        {
-            m_PlayerOnServer = m_PlayerNetworkObjects[m_ServerNetworkManager.LocalClientId][m_ClientNetworkManagers[0].LocalClientId].gameObject;
-            m_PlayerOnServerAnimator = m_PlayerOnServerAnimator = m_PlayerOnServer.GetComponent<Animator>();
-
-            m_PlayerOnClient = m_PlayerNetworkObjects[m_ClientNetworkManagers[0].LocalClientId][m_ClientNetworkManagers[0].LocalClientId].gameObject;
-            m_PlayerOnClientAnimator = m_PlayerOnClient.GetComponent<Animator>();
-
-            return base.OnServerAndClientsConnected();
-        }
-
-        // helper function to scan an animator and verify a given clip is present
-        private bool HasClip(Animator animator, string clipName)
-        {
-            var clips = new List<AnimatorClipInfo>();
-            animator.GetCurrentAnimatorClipInfo(0, clips);
-            foreach (var clip in clips)
-            {
-                if (clip.clip.name == clipName)
-                {
-                    return true;
-                }
-            }
-            return false;
-        }
-
-        [UnityTest]
-        public IEnumerator AnimationTriggerReset([Values(true, false)] bool asHash)
-        {
-            // We have "UnboundTrigger" purposely not bound to any animations so we can test resetting.
-            //  If we used a trigger that was bound to a transition, then the trigger would reset as soon as the
-            //  transition happens.  This way it will stay stuck on
-            string triggerString = "UnboundTrigger";
-            int triggerHash = Animator.StringToHash(triggerString);
-
-            // Verify trigger is off
-            Assert.True(m_PlayerOnServerAnimator.GetBool(triggerString) == false);
-            Assert.True(m_PlayerOnClientAnimator.GetBool(triggerString) == false);
-
-            // trigger.
-            if (asHash)
-            {
-                m_PlayerOnServer.GetComponent<NetworkAnimator>().SetTrigger(triggerHash);
-            }
-            else
-            {
-                m_PlayerOnServer.GetComponent<NetworkAnimator>().SetTrigger(triggerString);
-            }
-
-            // verify trigger is set for client and server
-            yield return WaitForConditionOrTimeOut(() => asHash ? m_PlayerOnServerAnimator.GetBool(triggerHash) : m_PlayerOnServerAnimator.GetBool(triggerString));
-            Assert.False(s_GlobalTimeoutHelper.TimedOut, "Timed out on server trigger set check");
-
-            yield return WaitForConditionOrTimeOut(() => asHash ? m_PlayerOnClientAnimator.GetBool(triggerHash) : m_PlayerOnClientAnimator.GetBool(triggerString));
-            Assert.False(s_GlobalTimeoutHelper.TimedOut, "Timed out on client trigger set check");
-
-            // reset the trigger
-            if (asHash)
-            {
-                m_PlayerOnServer.GetComponent<NetworkAnimator>().ResetTrigger(triggerHash);
-            }
-            else
-            {
-                m_PlayerOnServer.GetComponent<NetworkAnimator>().ResetTrigger(triggerString);
-            }
-
-            // verify trigger is reset for client and server
-            yield return WaitForConditionOrTimeOut(() => asHash ? m_PlayerOnServerAnimator.GetBool(triggerHash) == false : m_PlayerOnServerAnimator.GetBool(triggerString) == false);
-            Assert.False(s_GlobalTimeoutHelper.TimedOut, "Timed out on server reset check");
-
-            yield return WaitForConditionOrTimeOut(() => asHash ? m_PlayerOnClientAnimator.GetBool(triggerHash) == false : m_PlayerOnClientAnimator.GetBool(triggerString) == false);
-            Assert.False(s_GlobalTimeoutHelper.TimedOut, "Timed out on client reset check");
-        }
-
-
-        [UnityTest]
-        public IEnumerator AnimationStateSyncTest()
-        {
-            // check that we have started in the default state
-            Assert.True(m_PlayerOnServerAnimator.GetCurrentAnimatorStateInfo(0).IsName("DefaultState"));
-            Assert.True(m_PlayerOnClientAnimator.GetCurrentAnimatorStateInfo(0).IsName("DefaultState"));
-
-            // cause a change to the AlphaState state by setting AlphaParameter, which is
-            //  the variable bound to the transition from default to AlphaState (see the TestAnimatorController asset)
-            m_PlayerOnServerAnimator.SetBool("AlphaParameter", true);
-
-            // ...and now we should be in the AlphaState having triggered the AlphaParameter
-            yield return WaitForConditionOrTimeOut(() => m_PlayerOnServerAnimator.GetCurrentAnimatorStateInfo(0).IsName("AlphaState"));
-            Assert.False(s_GlobalTimeoutHelper.TimedOut, "Server failed to reach its animation state");
-
-            // ...and now the client should also have sync'd and arrived at the correct state
-            yield return WaitForConditionOrTimeOut(() => m_PlayerOnClientAnimator.GetCurrentAnimatorStateInfo(0).IsName("AlphaState"));
-            Assert.False(s_GlobalTimeoutHelper.TimedOut, "Client failed to sync its animation state from the server");
-        }
-
-        [UnityTest]
-        public IEnumerator AnimationLayerStateSyncTest()
-        {
-            int layer = 1;
-            // check that we have started in the default state
-            Assert.True(m_PlayerOnServerAnimator.GetCurrentAnimatorStateInfo(layer).IsName("DefaultStateLayer2"));
-            Assert.True(m_PlayerOnClientAnimator.GetCurrentAnimatorStateInfo(layer).IsName("DefaultStateLayer2"));
-
-            // cause a change to the AlphaState state by setting AlphaParameter, which is
-            //  the variable bound to the transition from default to AlphaState (see the TestAnimatorController asset)
-            m_PlayerOnServerAnimator.SetBool("Layer2AlphaParameter", true);
-
-            // ...and now we should be in the AlphaState having triggered the AlphaParameter
-            yield return WaitForConditionOrTimeOut(() => m_PlayerOnServerAnimator.GetCurrentAnimatorStateInfo(layer).IsName("Layer2AlphaState"));
-            Assert.False(s_GlobalTimeoutHelper.TimedOut, "Server failed to reach its animation state");
-
-            // ...and now the client should also have sync'd and arrived at the correct state
-            yield return WaitForConditionOrTimeOut(() => m_PlayerOnClientAnimator.GetCurrentAnimatorStateInfo(layer).IsName("Layer2AlphaState"));
-            Assert.False(s_GlobalTimeoutHelper.TimedOut, "Client failed to sync its animation state from the server");
-        }
-
-        [UnityTest]
-        public IEnumerator AnimationLayerWeightTest()
-        {
-            int layer = 1;
-            float targetWeight = 0.333f;
-
-            // check that we have started in the default state
-            Assert.True(Mathf.Approximately(m_PlayerOnServerAnimator.GetLayerWeight(layer), 1f));
-            Assert.True(Mathf.Approximately(m_PlayerOnClientAnimator.GetLayerWeight(layer), 1f));
-
-            m_PlayerOnServerAnimator.SetLayerWeight(layer, targetWeight);
-
-            // ...and now we should be in the AlphaState having triggered the AlphaParameter
-            yield return WaitForConditionOrTimeOut(() =>
-                Mathf.Approximately(m_PlayerOnServerAnimator.GetLayerWeight(layer), targetWeight)
-            );
-            Assert.False(s_GlobalTimeoutHelper.TimedOut, "Server failed to reach its animation state");
-
-            // ...and now the client should also have sync'd and arrived at the correct state
-            yield return WaitForConditionOrTimeOut(() =>
-                Mathf.Approximately(m_PlayerOnClientAnimator.GetLayerWeight(layer), targetWeight)
-            );
-            Assert.False(s_GlobalTimeoutHelper.TimedOut, "Server failed to reach its animation state");
-        }
-
-
-        [UnityTest]
-        public IEnumerator AnimationStateSyncTriggerTest([Values(true, false)] bool asHash)
-        {
-            string triggerString = "TestTrigger";
-            int triggerHash = Animator.StringToHash(triggerString);
-
-            // check that we have started in the default state
-            Assert.True(m_PlayerOnServerAnimator.GetCurrentAnimatorStateInfo(0).IsName("DefaultState"));
-            Assert.True(m_PlayerOnClientAnimator.GetCurrentAnimatorStateInfo(0).IsName("DefaultState"));
-
-            // cause a change to the AlphaState state by setting TestTrigger
-            //  note, we have a special test for triggers because activating triggers via the
-            //  NetworkAnimator is special; for other parameters you set them on the Animator and NetworkAnimator
-            //  listens.  But because triggers are super short and transitory, we require users to call
-            //  NetworkAnimator.SetTrigger so we don't miss it
-            if (asHash)
-            {
-                m_PlayerOnServer.GetComponent<NetworkAnimator>().SetTrigger(triggerHash);
-            }
-            else
-            {
-                m_PlayerOnServer.GetComponent<NetworkAnimator>().SetTrigger(triggerString);
-            }
-
-            // ...and now we should be in the AlphaState having triggered the AlphaParameter
-            yield return WaitForConditionOrTimeOut(() => m_PlayerOnServerAnimator.GetCurrentAnimatorStateInfo(0).IsName("TriggeredState"));
-            Assert.False(s_GlobalTimeoutHelper.TimedOut, "Server failed to reach its animation state via trigger");
-
-            // ...and now the client should also have sync'd and arrived at the correct state
-            yield return WaitForConditionOrTimeOut(() => m_PlayerOnClientAnimator.GetCurrentAnimatorStateInfo(0).IsName("TriggeredState"));
-            Assert.False(s_GlobalTimeoutHelper.TimedOut, "Client failed to sync its animation state from the server via trigger");
-        }
-
-        [UnityTest]
-        public IEnumerator AnimationStateSyncTestWithOverride()
-        {
-            // set up the animation override controller
-            var overrideController = Resources.Load("TestAnimatorOverrideController") as AnimatorOverrideController;
-            m_PlayerOnServer.GetComponent<Animator>().runtimeAnimatorController = overrideController;
-            m_PlayerOnClient.GetComponent<Animator>().runtimeAnimatorController = overrideController;
-
-            // in our default state, we should see the OverrideDefaultAnimation clip
-            Assert.True(HasClip(m_PlayerOnServerAnimator, "OverrideDefaultAnimation"));
-            Assert.True(HasClip(m_PlayerOnClientAnimator, "OverrideDefaultAnimation"));
-
-            // cause a change to the AlphaState state by setting AlphaParameter, which is
-            //  the variable bound to the transition from default to AlphaState (see the TestAnimatorController asset)
-            m_PlayerOnServerAnimator.SetBool("AlphaParameter", true);
-
-            // ...and now we should be in the AlphaState having set the AlphaParameter
-            yield return WaitForConditionOrTimeOut(() => HasClip(m_PlayerOnServerAnimator, "OverrideAlphaAnimation"));
-            Assert.False(s_GlobalTimeoutHelper.TimedOut, "Server failed to reach its overriden animation state");
-
-            // ...and now the client should also have sync'd and arrived at the correct state
-            yield return WaitForConditionOrTimeOut(() => HasClip(m_PlayerOnServerAnimator, "OverrideAlphaAnimation"));
-            Assert.False(s_GlobalTimeoutHelper.TimedOut, "Client failed to reach its overriden animation state");
-        }
-    }
-}
-#endif // COM_UNITY_MODULES_ANIMATION

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