Environment

Microsoft Visual Studio Community 2022 (64-bit) - Current
Version 17.9.2

.NET version

.NET 8

Did this work in a previous version of Visual Studio and/or previous .NET release?

Yes it worked in .NET Framework

Issue description

UserControls with type parameters cannot be designed in .NET Core

Steps to reproduce

https://github.com/janseris/WinFormsGenericUserControlDesignerTest
And open designer for all UserControls in the NetCore projct