After updating to plasma 5.13 the display is flickering before entering a plasma session. The screen is flickering, too, when I click on the menu and I sometimes see some very quick artefacts all the time when minimizing/maximizing programs.
I am very disappointed by this plasma version. I read that other distros had problems with it, too, and now I understand why did you postpone so much the change to 5.13.
Is there anything to do?