Xp-pen driver broke layout switching

A while ago, I used to have a xp-pen screen for drawing and installed their official driver in order for it to work
However, when I removed this driver from an autostart from /etc/xdg/autostart it broke my layout switching and until I change some keyboard settings in KDE, switching doesn’t work.
It doesn’t matter what setting to change either, so lately I switch “numlock status on startup” since it is the first to come up there.

Then I deleted this driver altogether (using their script) which didn’t solve the problem either

I tried finding any info regarding this problem to no avail
at first I thought the problem was with KDE, so I filled the bugreport there with no luck
I tried to contact xp-pen themselves, they promised to forward my request to the engineers and notify me about any info and I didn’t hear from them since april.
So the only hope for me now is to ask here and try to get to the root of the problem
I examined the install and uninstall script and didn’t find anything that could point to a clue
As far as I can tell, uninstall script deletes everything that was installed, aside from udev rule file (which I deleted then manually, just to be sure)