XamlC error XC0000 when using VisualState on custom control

[APopatanasov]

Description

I have a custom control with a VisualState defined in XAML. When XamlC runs during compilation, it throws the following error: XamlC error XC0000: Cannot resolve type "http://schemas.microsoft.com/dotnet/2021/maui:MyButton"

Steps to Reproduce

1. Create a custom control named MyButton that inherits from Button.
2. Declare the XML namespace (xmlns) for MyButton in your XAML file.
3. Use MyButton in XAML and define a VisualState for it.
4. Build the project.

Link to public reproduction project repository

https://github.com/telerik/ms-samples/tree/main/Maui/XamlCNet10Preview7Issue

Version with bug

10.0.0-preview.7

Is this a regression from previous behavior?

Yes, this used to work in .NET MAUI

Last version that worked well

10.0.0-preview.6

Affected platforms

iOS, Android, Windows, macOS

Affected platform versions

No response

Did you find any workaround?

No.

[NafeelaNazhir]

The issue has been verified in Visual Studio Code 1.103.0 with MAUI Version 10.0.0-preview.7.25406.3 It can be reproduced on the Android, iOS, Catalyst and Windows Platforms. Also it does not reproduced on 10.0.0-preview 6.