Hi! Window border glitches appears after long time in kde4 session. I tried to change engine to native/raster, set openGL to lower versions, but nothing of these helped me. I noticed that weird glitches disappearing when I disable Blur effect in Desktop Effects. I use x11-drivers/nvidia-drivers-355.06-r1. I'll attach screenshoot that describes about that bug more understandable Reproducible: Always Steps to Reproduce: 1. Login to kde4-session and enable Blur effect 2. Working with session as usually 3. Disable blur in Effects tab of Desktop effects, when you'll notice mentioned glitches 4. Enable it again and when opening another app (e.g. Dolphin) you can see glitch above at upper border of window. Expected Results: These glitches shouldn't be happened when blur is active https://paste.kde.org/psfm7ibhl Kwin Support Information http://i.imgur.com/De98vlE.png Screenshot that describes the problem
Created attachment 94463 [details] Glitch on window border
Created attachment 94464 [details] Kwin support info
Thank you for your bug report. Unfortunately you reported against a 4.x version which is nowadays unsupported. Given that your bug is impossible to be investigated and even fixed. Too many things have changed since the version you use. Please test again with a recent version of KWin (e.g. 5.4). If the problem is still visible please reopen. If you need user support for trying to mitigate the problem, please use forum.kde.org.
This looks like junk in the shadow texture (while I thought oxygen combined shadow and border) - Have you tried whether running w/o the blur effect actually makes the issue inreproducible (and the problem isn't simply cleared by reloading the compositor)? - does the texture junk stay a) in position b) with the window border when a) moving the window? b) moving another window 1. on top 2. below it - set the tearing prevention to either "only when cheap" or "full scene repaints" so that we stay away from the frontbuffer.
(In reply to Thomas Lübking from comment #4) > This looks like junk in the shadow texture (while I thought oxygen combined > shadow and border) > > - Have you tried whether running w/o the blur effect actually makes the > issue inreproducible (and the problem isn't simply cleared by reloading the > compositor)? > > - does the texture junk stay > a) in position > b) with the window border > when > a) moving the window? > b) moving another window > 1. on top > 2. below it > > - set the tearing prevention to either "only when cheap" or "full scene > repaints" so that we stay away from the frontbuffer. Reloading compositor "solves" the problem of blur for short time only. I can't determined definitely what is causing that weird issue.
(In reply to Thomas Lübking from comment #4) > - does the texture junk stay > a) in position > b) with the window border > when > a) moving the window? > b) moving another window > 1. on top > 2. below it It appears below it or on top, randomly, when I open, minimize or maximize the window, but often it is on top. Yes, junk stay in position with the window border and disappears for short time when I move the window .
It will hide during movement because of the wobbly window effect (which should disable blurring) Seems like some shadow texture gets polluted by blurring (do the artifacts match some blurred region on your screen?) - but I lack any idea "why". Does > after long time in kde4 session perhaps include suspends to ram (and wake-ups)?