[BUG] ShowPopupAsync deadlock when ShellNavigatingEventArgs is Cancelled

[sbloomztf]

Is there an existing issue for this?

• I have searched the existing issues

Did you read the "Reporting a bug" section on Contributing file?

• I have read the "Reporting a bug" section on Contributing file: https://github.com/CommunityToolkit/Maui/blob/main/CONTRIBUTING.md#reporting-a-bug

Current Behavior

Calling Shell.Current.ShowPopupAsync() will hang indefinitely when ShellNavigatingEventArgs is cancelled.

Example
protected override void OnNavigating(ShellNavigatingEventArgs args) { args.Cancel(); }

Expected Behavior

An Exception should be thrown.

Steps To Reproduce

1. Override OnNavigating of Shell
2. Call Cancel on ShellNavigatingEventArgs
3. Hang forever

protected override void OnNavigating(ShellNavigatingEventArgs args)
{
args.Cancel();
}

Link to public reproduction project repository

TODO

Environment

- .NET MAUI CommunityToolkit:
 14.0.1
- OS:
 Windows
- .NET MAUI:
10.0.41

Anything else?

No response