Hi, I like to look at the 5.0.2 development todo list. Its impressing to watch how these issues are handled !
I saw an issue related to kwin. I can not help with real new information but I would like to mention the following:
During the last years I got an always increasing amount of kwin-failure messages. Not only with KiCad but with many other programs. kwin-failures became daily business to me.
Matter of fact, this is one reason I left KDE after many years and switched to GNOME (Linux Mint Cinammon). I was also surprised that my old ATHLON64 runs dramatically faster without KDE.
So, if the KiCad developers find a workaround it is certainly a good thing but I also think the KDE people have to return to a “less features/eyecandy - more stable” philosophy.