AdditionalAssemblies not working properly in new version of Blazor Web App

[Alerinos]

Is there an existing issue for this?

• I have searched the existing issues

Describe the bug

While migrating to the new version of the Blazor App I encountered a problem, when using AdditionalAssemblies then pages from other solutions do not work.

<Router AppAssembly="@typeof(App).Assembly"
            AdditionalAssemblies="new[] { typeof(RazorClassLibrary1.Test).Assembly }">

Repository:
https://github.com/Alerinos/AdditionalAssembliesBug

Expected Behavior

No response

Steps To Reproduce

No response

Exceptions (if any)

No response

.NET Version

8 preview 6

Anything else?

No response

[mkArtakMSFT]

Thanks for contacting us. We think this will be addressed as part of #49756