Merge remote-tracking branch 'upstream/prerelease/2.3.0_stabilization' into configurator230

Author: davidkline-ms

Documentation/Images/ReleaseNotes/ApiCompatibilityLevel.png

@@ -5,7 +5,6 @@ The Microsoft Mixed Reality Toolkit is provided as a collection of packages. The
 - [Foundation](#foundation)
 - [Extensions](#extensions)
 - [Tools](#tools)
-- [Providers.UnityAR](#providersunityar)
 - [Examples](#examples)
 
 ## Foundation
@@ -18,8 +17,10 @@ The Microsoft.MixedRealityToolkit.Unity.Foundation package includes the core com
 | MixedRealityToolkit.Providers | | |
 | | [ObjectMeshObserver](SpatialAwareness/SpatialObjectMeshObserver.md) | Spatial awareness observer using a 3D model as the data. |
 | | OpenVR | Support for OpenVR devices. |
+| | [UnityAR](CameraSystem/UnityArCameraSettings.md) | (Experimental) Camera settings provider enabling MRTK use with mobile AR devices. |
 | | WindowsMixedReality | Support for Windows Mixed Reality devices, including Microsoft HoloLens and immersive headsets. |
 | | WindowsVoiceInput | Support for speech and dictation on Microsoft Windows platforms. |
+| | XRSDK | (Experimental) Support for [Unity's new XR framework](https://blogs.unity3d.com/2020/01/24/unity-xr-platform-updates/) in Unity 2019.3. |
 | MixedRealityToolkit.SDK | | |
 | | Experimental | Experimental features, including shaders, user interface controls and individual system managers. |
 | | Features | Functionality that builds upon the Foundation package. |
@@ -40,12 +41,13 @@ The Microsoft.MixedRealityToolkit.Unity.Foundation package includes the core com
 
 The optional Microsoft.MixedRealityToolkit.Unity.Extensions package includes additional services that extend the functionality of the Microsoft Mixed Reality Toolkit.
 
-> [!Note]
+> [!NOTE]
 > The extensions package requires Microsoft.MixedRealityToolkit.Unity.Foundation.
 
 | Folder | Component | Description |
 | --- | --- | --- |
 | MixedRealityToolkit.Extensions | |
+| | HandPhysicsService | Service that adds physics support to articulated hands. |
 | | LostTrackingService | Service that simplifies handing of tracking loss on Microsoft HoloLens devices. |
 | | [SceneTransitionService](Extensions/SceneTransitionService/SceneTransitionServiceOverview.md) | Service that simplifies adding smooth scene transitions. |
 
@@ -54,7 +56,7 @@ The optional Microsoft.MixedRealityToolkit.Unity.Extensions package includes add
 The optional Microsoft.MixedRealityToolkit.Unity.Tools package includes helpful tools that enhance the mixed reality development experience using the Microsoft Mixed Reality Toolkit.
 These tools are located in the **Mixed Reality Toolkit > Utilities** menu in the Unity Editor.
 
-> [!Note]
+> [!NOTE]
 > The tools package requires Microsoft.MixedRealityToolkit.Unity.Foundation.
 
 | Folder | Component | Description |
@@ -68,21 +70,11 @@ These tools are located in the **Mixed Reality Toolkit > Utilities** menu in the
 | | ScreenshotUtility | Enables capturing application images in the Unity editor. |
 | | TextureCombinerWindow | Utility to combine graphics textures. |
 
-## Providers.UnityAR
-
-> [!Note]
-> The UnityAR package requires Microsoft.MixedRealityToolkit.Unity.Foundation.
-
-| Folder | Component | Description |
-| --- | --- | --- |
-| MixedRealityToolkit.Staging | | |
-| | [UnityAR](CameraSystem/UnityArCameraSettings.md) | Camera settings provider enabling MRTK use with mobile AR devices. |
-
 ## Examples
 
 The optional Microsoft.MixedRealityToolkit.Unity.Examples package includes demonstration projects that illustrate the features of the Microsoft Mixed Reality Toolkit.
 
-> [!Note]
+> [!NOTE]
 > The examples package requires Microsoft.MixedRealityToolkit.Unity.Foundation.
 
 | Folder | Component | Description |

Documentation/Images/ReleaseNotes/DuplicateDependencies.png

@@ -12,6 +12,8 @@
 - [What's new](#whats-new-in-230)
 - [Known issues](#known-issues-in-230)
 
+This release of the Microsoft Mixed Reality Toolkit supports the following devices and platforms.
+
 - Microsoft HoloLens 2
 - Microsoft HoloLens (1st gen)
 - Windows Mixed Reality Immersive headsets
@@ -148,6 +150,26 @@ We are hoping to eventually deprecate ManipulationHandler and BoundingBox in fav
 
 ### Known issues in 2.3.0
 
+**CS0579: Duplicate 'AssemblyVersion' attribute**
+
+After enabling MSBuild for Unity, if Player Settings > Other Settings > API Compatibility Level is changed, Unity may report a large number of errors in project script files. Notably, there will be one or more CS0579 errors stating that there is a duplicate AssemblyVersion attribute.
+
+This is caused by an issue in MSBuild for Unity ([#133](https://github.com/microsoft/MSBuildForUnity/issues/133)) where it is not properly removing dependency packages before restoring.
+
+To resolve these errors:
+
+- In the **Project** window, expand **Dependencies**
+- Open **Edit** > **Project Settings** > **Player**
+- Expand **Other Settings**
+- Examine the value of **Api Compatibility Level**
+
+    ![API Compatibility Level](Images/ReleaseNotes/ApiCompatibilityLevel.png)
+
+- If set to **.NET Standard 2.0**, delete the **Dependencies\net46** folder
+- If set to **.NET 4.x**, delete the **Dependencies\netstandard20** folder
+
+    ![Duplicate dependencies](Images/ReleaseNotes/DuplicateDependencies.png)
+
 **Issues with the Unity 2019.3 new XR platform on Windows Mixed Reality**
 
 The following issues are known when using the new XR platform and version **2.0.4 (preview.3)** of the Windows XR Plugin: