The problem of using WPF-UI on the .NET Framework 4.8

[Arhkeis]

Describe the bug

When using WPF-UI in a new project using .NET Framework 4.8, I cannot use the documentation and examples of codes, since they do not work.

To Reproduce

Any example of the implementation of NavigationView taken on the Internet for the .NET Framework 4.8 does not work here only if the .NET 8/9 versions.

Expected behavior

I tried to adapt the code for the .NET Framework 4.8 - the application is compiled without problems, but ControlContent or Frame transitions are not made.

Screenshots

No response

OS version

Windows 11 23H2

.NET version

.NET Framework 4.8

WPF-UI NuGet version

4.0.0

Additional context

I am a beginner in the development of WPF applications and use this package, since I really like it.
If I filled something incorrectly, please specify what exactly and I will provide everything.