Per Joethei:
Unfortunately it seems that the recent Electron update completely broke our previous approach. They introduced a new API that only supports win11 22H2+ but we aren’t too sure how well that works.
Transparency on Windows was using a previously undocumented Win API, which also has a nasty bug that makes the app not respond well to being moved around the screen.
It can be done with a plugin now, previously it required some native code which is why it was included in core.