Created attachment 103104 [details] Screenshot (icons blurred for privacy) After some amount of time (or due to some circumstance I cannot determine), the panel will "freeze", and get stuck displaying a very old image (from hours ago). Icons will no longer be updated or highlighted, but interaction works - clicking in the areas corresponding to the icons works fine, and even attempting to change panel settings works, but it *does not* make the panel update correctly. Compositing is enabled, with KWin set to OpenGL (tried both 2.0 and 3.1). Setting vsync to automatic, full or cheap doesn't change anything (haven't tried XRender or other vsync settings yet). A screenshot demonstrating the issue is attached. System setup: Fedora 25 x86_64 Plasma 5.8.4 KDE Frameworks 5.27.0 Qt 5.7.1 Linux 4.8.15 NVIDIA proprietary drivers (375.26)
I have this issue too, on Kubuntu 16.10 with the Kubuntu backports PPA (KDE Frameworks 5.28.0, Plasma 5.8.4, using X11, Intel Kaby Lake). For me, the entire screen freezes, but the cursor still appears to work (i.e., if there is text on the page, the 'I' cursor appears. If it's a link, the hand cursor appears. If I change the window, the cursor matches the state of the new window).
Edit: In my case, it's not an old image that is displayed, but the most recent frame displayed.
Sounds like this bug: https://bugs.kde.org/show_bug.cgi?id=373427 You can confirm it by either forcing DRI3 rendering (see comment #19) or upgrading to xorg 1.19.1 If it turns out to be something else, please reopen this bug. *** This bug has been marked as a duplicate of bug 373427 ***