Version: (using KDE Devel) Installed from: Compiled sources OS: Linux I think this bug was introduced around 3-4 days ago, the title explains it all. Open a konsole window with different tabs and switch between them, the panel taskbar title does not update until mouseover. I also see something similar when windows are opening, sometimes the fade does not repaint until mouseover. I get the same problem if compositing is disabled.
It wasn't introduced a few days ago. It just became much more apparent. The fact that startup notifications were/are just blank areas was/is actually exactly the same issue. *** This bug has been marked as a duplicate of 154147 ***