After uninstalling py5mode on Windows, Thonny is broken

[codeanticode]

I uninstalled py5mode, and upon restarting Thonny I got the following error:

After closing this error, the IDE is frozen.

But then I uninstalled and re-installed Thonny, and the same error comes up - I even manually deleted the AppData/Local/Programs/Thonny folder before uninstalling and still the same error comes up, so effectively making Thonny unusable. Tested on Windows 10.

[tabreturn]

You're using Windows, I assume? Delete the \AppData\Roaming\Thonny folder (or, more specifically, edit/delete the configuration.ini file therein).

Thonny won't default to another theme if the one you've applied is missing. By uninstalling thonny-py5mode, you've effectively deleted the active theme (Kyanite). However, this issue is fixed in Thonny 4: thonny/thonny#2149

Note that thonny-py5mode won't run on Thonny 4 until JPype adds wheels for Python 3.10 (probably quite soon).