SUMMARY A blue flickering line is shown above the panel when its height is set to certain sizes. Line seems one or two pixels thick. STEPS TO REPRODUCE 1. Enter edit mode and set panel height to 38 2. Observe a blue line on top of the bar (see screenshot1.png) 3. Open and maximize any app (e.g. Firefox). Line starts to flicker when scrolling. OBSERVED RESULT Small but annoying blue line in the panel. This behavior only happens for certain heights (e.g. 34, 38, etc.). For other heights panel works just fine (e.g. 36, 40, etc.) EXPECTED RESULT Any panel height should work without adding artifacts. SOFTWARE/OS VERSIONS Operating System: Arch Linux KDE Plasma Version: 5.26.90 KDE Frameworks Version: 5.102.0 Qt Version: 5.15.8 Kernel Version: 6.1.6-arch1-3 (64-bit) Graphics Platform: Wayland Processors: 8 × 11th Gen Intel® Core™ i5-1135G7 @ 2.40GHz Memory: 15.4 GiB of RAM Graphics Processor: Mesa Intel® Xe Graphics Manufacturer: LENOVO Product Name: 20XYCTO1WW System Version: ThinkPad X1 Yoga Gen 6
Created attachment 155440 [details] Screenshot showing blue line in panel
Probably this video is more helpful than the text in the bug report ;) https://drive.switch.ch/index.php/s/0rR2j7871Sf0sG1
What scale factor are you using? And is Firefox using XWayland in that video, or is it in native Wayland mode? If it's using XWayland, can you try again with Firefox forced to native Wayland mode, or another app you know to be native-wayland-compatible (like System Settings or Dolphin, or almost any other KDE app)?
(In reply to Nate Graham from comment #3) > What scale factor are you using? And is Firefox using XWayland in that > video, or is it in native Wayland mode? If it's using XWayland, can you try > again with Firefox forced to native Wayland mode, or another app you know to > be native-wayland-compatible (like System Settings or Dolphin, or almost any > other KDE app)? 125% and Firefox is in native Wayland mode.
Cool. Thanks. Does the problem completely vanish if you use 100% scale? Are XWayland windows affected, or other native Wayland windows besides Firefox?
(In reply to Nate Graham from comment #5) > Cool. Thanks. > > Does the problem completely vanish if you use 100% scale? No, I cannot reproduce with 100% scale. > Are XWayland windows affected, or other native Wayland windows besides > Firefox? Yes, the only difference is how much the line flicks. With other apps (e.g. Kate or Dolphin), line remains visible all the time instead of flickering like with Firefox.
I see a thin line on top of the bottom panel since 5.26.90. Top panel looks fine. 4k at 175%. (first picture in gallery link bellow) Setting the 4k display to 100% (no scaling) moves the line to the left edge of the panel. (second picture in gallery link bellow) Other instances: opening systray items for the first time (4k at 175%). (third picture in gallery link bellow) Gallery of images showing the issue: https://imgur.com/a/ieKqyG1 Operating System: EndeavourOS KDE Plasma Version: 5.26.90 KDE Frameworks Version: 5.102.0 Qt Version: 5.15.8 Kernel Version: 6.2.0-rc4-273-tkg-cfs (64-bit) Graphics Platform: Wayland Graphics Processor: Mesa Intel® Arc
(In reply to Schlaefer from comment #7) > I see a thin line on top of the bottom panel since 5.26.90. Top panel looks Forgot to mention: The lines I see are not flickering but static.
*** Bug 464940 has been marked as a duplicate of this bug. ***
What happens if you disable the blur and/or contrast effects? Does disabling either of them get rid of the line?
(In reply to Arjen Hiemstra from comment #10) > What happens if you disable the blur and/or contrast effects? Does disabling > either of them get rid of the line? Yes! Disabling "Background Constrast" effect solves the issue. Disabling blur does not make a difference. Also, I just noticed that the issue is also visible (although quite less noticeable) in plasma notifications and other menus.
I can confirm, disabling "Background Contrast" makes it disappear.
*** Bug 465792 has been marked as a duplicate of this bug. ***
*** Bug 465833 has been marked as a duplicate of this bug. ***
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I'm getting an almost identical issue (Wayland, 150% scaling), but disabling Background Contrast doesn't fix it.
(In reply to poperigby from comment #17) > I'm getting an almost identical issue (Wayland, 150% scaling), but disabling > Background Contrast doesn't fix it. The same.the problem only occurs when I use wayland session and use 150% scaling, 145% and 155% are normal
*** This bug has been marked as a duplicate of bug 465158 ***
Git commit edbbe996d33d17ae8020fb06611141586fd1e7bb by Vlad Zahorodnii, on behalf of Arjen Hiemstra. Committed on 21/02/2023 at 07:50. Pushed by vladz into branch 'master'. effects/contrast: Round device coordinates when creating geometry Since normal geometry is now rounded, we need to make sure to round anything that should match that geometry, otherwise we risk things peeking out of the normal geometry. M +4 -4 src/effects/backgroundcontrast/contrast.cpp https://invent.kde.org/plasma/kwin/commit/edbbe996d33d17ae8020fb06611141586fd1e7bb
Git commit c3f88fed6211c6023863a749736280733333f970 by Vlad Zahorodnii, on behalf of Arjen Hiemstra. Committed on 21/02/2023 at 09:08. Pushed by ahiemstra into branch 'Plasma/5.27'. effects/contrast: Round device coordinates when creating geometry Since normal geometry is now rounded, we need to make sure to round anything that should match that geometry, otherwise we risk things peeking out of the normal geometry. (cherry picked from commit edbbe996d33d17ae8020fb06611141586fd1e7bb) M +4 -4 src/effects/backgroundcontrast/contrast.cpp https://invent.kde.org/plasma/kwin/commit/c3f88fed6211c6023863a749736280733333f970
I confirm the patch fixes the issue for me.
*** Bug 465829 has been marked as a duplicate of this bug. ***
*** Bug 466155 has been marked as a duplicate of this bug. ***
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