MenuFlyout: `FlyoutBase.ShowAt` throws COMException

Describe the bug

For some users of my application, FlyoutBase.ShowAt throws an exception.
From what I can tell, this is not a permanent error, meaning it works the next time they try (I only see one crash report per user).

Steps to reproduce the bug

var menuFlyout = new MenuFlyout();
// ...add some menu items to the menu flyou
menuFlyout.ShowAt(button, new FlyoutShowOptions() { Placement = FlyoutPlacementMode.Bottom });

Actual behavior

System.Runtime.InteropServices.COMException (0x80004005)
   at WinRT.ExceptionHelpers.<ThrowExceptionForHR>g__Throw|38_0(Int32) + 0x42
   at ABI.Microsoft.UI.Xaml.Controls.Primitives.IFlyoutBaseMethods.ShowAt(IObjectReference, DependencyObject, FlyoutShowOptions) + 0xfe
   at MyApp.MyMethod() + 0x38a

Expected behavior

No Crash

Screenshots

No response

NuGet package version

WinUI 3 - Windows App SDK 1.7.3: 1.7.250606001

Windows version

No response

Additional context

Multiple Windows versions are affected:
10.0.19045
10.0.22631
10.0.26100

Start with the MenuFlyout.ShowAt call and the FlyoutBase.ShowAt entry in the reported stack trace, then investigate the intermittent COMException on Windows 10.0.19045, 10.0.22631, and 10.0.26100. Done means identifying a reproducible cause or validated fix for the reported scenario, with coverage for the failing behavior.