[.NET MAUI 9.0 Preview 4] Windows .NET MAUI App throws a "combase.dll: A fail fast exception occurred" upon making a grid visible on Windows

[janne-hmp]

Describe the bug

I tried to check how my app translates to Windows (WinUI3) using .NET MAUI 9.0 Preview 4. It works generally fine on Android and iOS, but on Windows / WinUI3 I get "combase.dll: A fail fast exception occurred. Exception handlers will not be invoked and the process will be terminated immediately." upon making a grid visible on one the pages (MenuGrid on GamePage via ShowMenuCanvas function). The call stack is quite useless with external code, so there is no obvious way to start debugging the situation. Does anybody know what might be causing this in WinUI3 in .NET MAUI?

Steps to reproduce the bug

1. Clone GnollHack repository and build GnollHackM (.NET MAUI 9.0 project)
2. Start the app on Windows and press Play Game
3. The app crashes after asking for player name. Debugger reports an exception in external code: "combase.dll: A fail fast exception occurred. Exception handlers will not be invoked and the process will be terminated immediately."

Expected behavior

The app does not throw an exception.

Screenshots

No response

NuGet package version

None

Windows version

Windows 11 (22H2): Build 22621

Additional context

.NET MAUI target framework is net9.0-windows10.0.19041.0

[github-actions]

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Please view the issues below to see if they solve your problem, and if the issue describes your problem please consider closing this one. Thank you!

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[janne-hmp]

Seemed to be a problem with trying to call a non-exported function from the DLL.