Hi, When switching to another application its window is drawn but just as it should be fully ready, input (mouse, keyboard, touchpad) for it is not responsive. Wait 5 to 10 seconds and it is responsive. Or send it a wakeup signal by Alt+tabbing and returning to it. After wake up, the input buffer (keystrokes etc if any) are flushed to the window. Reproducible: Always Steps to Reproduce: 1. Open a bunch of applications 2. Switch using Alt+tab randomly 3. It is the case that sometimes (more than %50) you have to wait for around 7 seconds to begin working with the application Actual Results: You have to wait around 7 seconds until the activated window is responsive. Expected Results: You should have been immediately able to communicate with the switched to application. I have recently enabled activities (as virtual desktops) and also often connect to a second screen. It was not the case before this new setting.
could you please provide the output of: qdbus org.kde.KWin /KWin supportInformation
Created attachment 100868 [details] (OUTPUT) qdbus org.kde.KWin /KWin supportInformation Hi, KWin information attached.
> KWin version: 5.5.5 > Qt Version: 5.5.1 Please upgrade to newer version of both Plasma an Qt. Especially Qt is rather old and known to have had issues. There is a fair amount of chance that the problem is fixed with newer versions. Also it's close to impossible for us to investigate for such old software.