Cannot assign to Region.Attached in the new UWP application

[ttustonic]

Current behavior

Setting uen:Region.Attached="true" on Grid (or NavigationView) throws Windows.UI.Xaml.Markup.XamlParseException:
Failed to assign to property 'Uno.Extensions.Navigation.UI.Region.Attached'.

Expected behavior

Should not throw any exception

How to reproduce it (as minimally and precisely as possible)

1. Create a new UWP application from the VS wizard or command line.
2. add xmlns:uen="using:Uno.Extensions.Navigation.UI"
3. add uen:Region.Attached="true" to the grid in MainPage.xaml: <Grid uen:Region.Attached="true">
4. Run the app. Exception is thrown in InitialiizeComponent

Environment

Nuget Package (s):

Package Version(s):

<PackageReference Include="Uno.Extensions.Navigation">
      <Version>4.2.2</Version>
    </PackageReference>
    <PackageReference Include="Uno.Extensions.Navigation.Toolkit.UI">
      <Version>4.2.2</Version>
    </PackageReference>
    <PackageReference Include="Uno.Extensions.Navigation.UI">
      <Version>4.2.2</Version>
    </PackageReference>

Affected platform(s):

• iOS
• macOS (AppKit)
• Mac Catalyst
• Android
• WebAssembly
• Windows
• Skia (WPF)
• Skia (GTK on Linux/macOS/Windows)
• Skia (Linux Framebuffer)
• Build tasks

Visual Studio:

• 2019 (version: )
• 2022 (version: )
• Visual Studio Code (version: )
• Rider Windows (version: )
• Rider macOS (version: )

Relevant plugins:

• Resharper (version: )

Anything else we need to know?

UnoUWPtest2.zip