WinRT class throws InvalidCastException on Desktop

[getrou]

In porting a library to WinUI3, a class started throwing an InvalidCastException.
It appears to fail trying to QI the class to an IDependencyObject.
This QI succeeds when done from a UAP but fails in a Desktop packaged app.

Version Info
CsWinRT 1.1.4
.NET SDK 10.0.19041.15
ProjectReunion.0.5.0-prerelease

[angelazhangmsft]

@getrou - Are you authoring a C#/WinRT component? I assume you are creating a C#/.NET5 class library, and consuming it in a C# desktop packaged app (Project Reunion)?

Would you be able to provide a repro?

[sutm]

I too am encountering invalid cast exception when porting to WinUI3 for a desktop application.
The following line causes the exception to be thrown:
var bitmap = new CanvasRenderTarget(canvasdevice, 16, 16, 96);

Stack trace:
at System.Runtime.InteropServices.Marshal.ThrowExceptionForHR(Int32 errorCode)
at WinRT.IObjectReference.As[T](Guid iid)
at WinRT.IObjectReference.As(Guid iid)
at Microsoft.UI.Xaml.DependencyObject..ctor(IObjectReference objRef)
at Microsoft.Graphics.Canvas.CanvasBitmap..ctor(IObjectReference objRef)
at Microsoft.Graphics.Canvas.CanvasRenderTarget..ctor(IObjectReference objRef)
at Microsoft.Graphics.Canvas.CanvasRenderTarget..ctor(ICanvasResourceCreator resourceCreator, Single width, Single height, Single dpi)

Microsoft.Graphics.Win2D v0.5.0.13
Microsoft. ProjectReunion v0.5.5
Microsoft.Windows.csWinRT v1.2.5

[getrou]

Updating, this was a WRL issue and not a cswinrt issue. I will publish an update to Win2D with a fix next week.