Hello. The problem: When I open some helping window of not maximized program (Dolphins settings window for example), or when I start any OpenGL game not in fullscreen, all areas around this window starts flickering. To stop this I must switch to other maximized window and back. I have same problem on different laptops, that uses different Intel graphics, don't know, is this happens only on Intel or not. I use default Kwin settings, but tried others to

I am experiencing this problem for a long time, don't remember, when it started in KDE5, but now I use latest KDE, and the problem still exists on all my computers. in different distributions. Although, I didn't found similar posts here, so, am I the only unlucky man in the universe?