Design not working?

From some time i cant you the RAD tool and cant make it work



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Am i missing something?

Can you elaborate? Does the problem happen in a new application?

No, just tested it
Made new app "Blazor Server Application" and just worked.
And runs the project too.
My old project stuck at


PS
my main dev tool is Visual Studio and everything works as it should

may be the problem is that i have multi project solution and/or my main project has dependance from other?