Mathcad Prime clipboard bug after NET 7.0 framework installing

I installed Mathcad Express (7.0 and 8.0 tested) on reseted windows 10 and it worked correctrly. As soon as I installed NET 7.0 (https://dotnet.microsoft.com/en-us/download/dotnet/thank-you/sdk-7.0.102-windows-x64-installer ) and rebooted the computer - a bug appeared:

- create a text field (Ctl+T), enter the text;

- enter the formula (Ctrl+Shift+M);

- select the text (Ctrl+C);

- paste the text - it is inserted without a formula (but if you copy only the formula, then it's copied correctly).

Strange things:

- The bug remains after NET 7.0 uninstalling. But I tried several times to reset windows 10 and after it bug is disapeared. And bug bring back every time after NET 7.0 installing and computer rebooting.

- All others clipboard operations works correctly - only pasting text+formula into text area works incorrectly.

Please give me a hint, what is special about this functional realization? Otherwise it is not clear what to write to NET developers in bugreport.