Hi there!
Not sure if this should go into help, because I am not sure if it has anything to do with KDE or Plasma.
I am using Arch and kde plasma with an nvidia 3090 and steam/proton and nvidia-dkms .
99% of the games work flawlessly but older games like civ3, civ4 and civ5 and shadowrun hong kong all have garbled graphics. (civ 6 works)
I already removed and reinstalled nvidia-dkms and tools, the system is current with all patches.
Does anyone have any ideas that could point me in the right direction what to do?
Screenshot: