I sometimes use an external screen on my laptop. It is configured with systemsettings to disable the integrated screen whenever a VGA gets connected. The screen I use has a different resolution than the integrated one, but also supports that resolution as non-native one. The screen will work fine but when I click on the plasma taskbar and try to use it to change task, the windows decoration disappear. However kwin doesn't actually crash, and I need to use killall -9 to actually kill the process so that I can spawn another instance of it. Reproducible: Always Steps to Reproduce: 1. Configure systemsettings so that only 1 screen is active at any time. 2. Plug an external screen 3. Click on the plasma bar to change active window
KWin crashes because of bug #341497 (should be fixed with Qt 5.6 and potentially affects each and every Qt5 application) and drkonqi will hold a stopped process because of bug #353428 (hopefully fixed with KWin 5.6) Duping to bug #353428 (which can occur for any crash), but do yourself a favor and do not touch the screen layout before Qt 5.6 - crashed me ksmserver (ie. the entire session) several times ... :-( *** This bug has been marked as a duplicate of bug 353428 ***