After my last update dialog boxes often stay drawn on the desktop. I believe they are actually finished but the image of them stays on the desktop background. They are inactive, none of the buttons work or highlight. The original action was completed. Is there a way short of logging out and back in that can redraw the screen? I've tried killing and kstarting plasmashell but that doesn't work.

KDE Frameworks 5.15.0
Qt 5.5.1 (built against 5.4.2)
The xcb windowing system

This will be the translucency effect, see https://bugs.kde.org/show_bug.cgi?id=342716

luebking wrote:This will be the translucency effect, see https://bugs.kde.org/show_bug.cgi?id=342716

Thanks. The dead dialog image does indeed go away when I turn off translucency, and the same stuck image comes back when I turn it back on. By any chance do you know a terminal command to force a proper redraw?

That's not related to redraws, the effect for some reason keeps the window referenced. Every redraw will redraw the texture of the gone dialog because the compositor believes it's still needed (otherwise, just moving another window in that area would be sufficient)
Unfortunately no developer was so far able to reproduce the problem.