Bug 503360

Summary: Weird 100% transparent thin line in apps like Kate and Konsole.
Product: [Plasma] kwin Reporter: krunkske <cas.vankrunkelsven>
Component: generalAssignee: KWin default assignee <kwin-bugs-null>
Status: RESOLVED FIXED    
Severity: normal CC: kdedev, strong.drum0546
Priority: NOR    
Version First Reported In: 6.3.4   
Target Milestone: ---   
Platform: Arch Linux   
OS: Linux   
Latest Commit: Version Fixed/Implemented In:
Sentry Crash Report:
Attachments: The Line in Konsole

Description krunkske 2025-04-25 18:11:37 UTC
SUMMARY

There is a weird 100% transparent line in some apps like Kate, Konsole and Kwrite. They don't seem to appear in apps like Firefox, Steam and Discord. Sometimes the line flickers too but that's very infrequent. The line always appears at the same height and goes away sometimes when more text goes over the line and always goes away when moving the window. I tried the same apps in a kwin_wayland session and a weston session. They don't appear in weston but they do appear in kwin_wayland. It has been there for a few months.



STEPS TO REPRODUCE
1. Open Kwrite, Konsole, Kate...
2. Do some stuff (execute commands, write text) until certain height until line appears. 

OBSERVED RESULT
There is a transparent line

EXPECTED RESULT
Line should not be there

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: 
KDE Plasma Version: 
KDE Frameworks Version: 
Qt Version: 

INFO CENTER
Operating System: EndeavourOS 
KDE Plasma Version: 6.3.4
KDE Frameworks Version: 6.13.0
Qt Version: 6.9.0
Kernel Version: 6.14.3-arch1-1 (64-bit)
Graphics Platform: Wayland
Processors: 12 × AMD Ryzen 5 7600 6-Core Processor
Memory: 30,5 GiB of RAM
Graphics Processor 1: AMD Radeon RX 7800 XT
Graphics Processor 2: AMD Radeon Graphics
Manufacturer: ASRock
Product Name: B650M Pro RS WiFi

KWin Support Information:

==========================

Version
=======
KWin version: 6.3.4
Qt Version: 6.9.0
Qt compile version: 6.9.0
XCB compile version: 1.17.0

Operation Mode: Wayland

Build Options
=============
KWIN_BUILD_DECORATIONS: yes
KWIN_BUILD_TABBOX: yes
KWIN_BUILD_ACTIVITIES: yes
HAVE_X11_XCB: yes
HAVE_GLX: yes

X11
===
Vendor: The X.Org Foundation
Vendor Release: 12401006
Protocol Version/Revision: 11/0
SHAPE: yes; Version: 0x11
RANDR: yes; Version: 0x14
DAMAGE: yes; Version: 0x11
Composite: yes; Version: 0x4
RENDER: yes; Version: 0xb
XFIXES: yes; Version: 0x50
SYNC: yes; Version: 0x31
GLX: yes; Version: 0x0

Decoration
==========
Plugin: org.kde.kwin.aurorae
Theme: __aurorae__svg__Slot-Blur-Dark-Aurorae-6
Plugin recommends border size: No
onAllDesktopsAvailable: false
alphaChannelSupported: true
closeOnDoubleClickOnMenu: false
decorationButtonsLeft: 0, 2
decorationButtonsRight: 6, 3, 4, 5
borderSize: 0
gridUnit: 10
font: Noto Sans,10,-1,0,400,0,0,0,0,0,0,0,0,0,0,1
smallSpacing: 2
largeSpacing: 10

Output backend
==============
Name: DRM
Atomic Mode Setting on GPU 0: true

Cursor
======
themeName: Breeze_Light
themeSize: 24

Options
=======
focusPolicy: ClickToFocus
xwaylandCrashPolicy: 1
xwaylandMaxCrashCount: 3
nextFocusPrefersMouse: false
clickRaise: true
autoRaise: false
autoRaiseInterval: 0
delayFocusInterval: 0
shadeHover: false
shadeHoverInterval: 250
separateScreenFocus: true
placement: 5
activationDesktopPolicy: SwitchToOtherDesktop
focusPolicyIsReasonable: true
borderSnapZone: 10
windowSnapZone: 10
centerSnapZone: 0
snapOnlyWhenOverlapping: false
edgeBarrier: 100
cornerBarrier: 1
rollOverDesktops: false
focusStealingPreventionLevel: 1
operationTitlebarDblClick: 5000
operationMaxButtonLeftClick: 5000
operationMaxButtonMiddleClick: 5015
operationMaxButtonRightClick: 5014
commandActiveTitlebar1: MouseRaise
commandActiveTitlebar2: MouseMinimize
commandActiveTitlebar3: MouseOperationsMenu
commandInactiveTitlebar1: MouseActivateAndRaise
commandInactiveTitlebar2: MouseNothing
commandInactiveTitlebar3: MouseOperationsMenu
commandWindow1: MouseActivateRaiseOnReleaseAndPassClick
commandWindow2: MouseActivateAndPassClick
commandWindow3: MouseActivateAndPassClick
commandWindowWheel: MouseNothing
commandAll1: MouseUnrestrictedMove
commandAll2: MouseToggleRaiseAndLower
commandAll3: MouseUnrestrictedResize
keyCmdAllModKey: 16777250
doubleClickBorderToMaximize: true
condensedTitle: false
electricBorderMaximize: true
electricBorderTiling: true
electricBorderCornerRatio: 0.25
borderlessMaximizedWindows: false
killPingTimeout: 5000
compositingMode: 1
useCompositing: true
hiddenPreviews: 1
glSmoothScale: 2
glStrictBinding: true
glStrictBindingFollowsDriver: true
glPreferBufferSwap: AutoSwapStrategy
glPlatformInterface: 2
windowsBlockCompositing: true
allowTearing: true
interactiveWindowMoveEnabled: true

Screen Edges
============
desktopSwitching: false
desktopSwitchingMovingClients: false
cursorPushBackDistance: 1x1
actionTopLeft: 0
actionTop: 0
actionTopRight: 0
actionRight: 0
actionBottomRight: 0
actionBottom: 0
actionBottomLeft: 5
actionLeft: 0

Screens
=======
Number of Screens: 1

Screen 0:
---------
Name: DP-2
Enabled: 1
Geometry: 0,0,2226x1252
Physical size: 597x336mm
Scale: 1.15
Refresh Rate: 143912
Adaptive Sync: never

Compositing
===========
Compositing is active
Compositing Type: OpenGL
OpenGL vendor string: AMD
OpenGL renderer string: AMD Radeon RX 7800 XT (radeonsi, navi32, LLVM 19.1.7, DRM 3.61, 6.14.3-arch1-1)
OpenGL version string: 4.6 (Core Profile) Mesa 25.0.4-arch1.1
OpenGL platform interface: EGL
OpenGL shading language version string: 4.60
Driver: Unknown
GPU class: Unknown
OpenGL version: 4.6
GLSL version: 4.60
Mesa version: 25.0.4
X server version: 1.24.1
Linux kernel version: 6.14.3
Direct rendering: Requires strict binding: no
Virtual Machine:  no
OpenGL 2 Shaders are used

Loaded Effects:
---------------
shakecursor
screenshot
outputlocator
colorpicker
zoom
screenedge
blur
contrast
logout
login
sessionquit
slidingpopups
windowaperture
translucency
slide
glide
fullscreen
dimscreen
frozenapp
fadingpopups
squash
maximize
sheet
dialogparent
windowview
tileseditor
overview
highlightwindow
blendchanges
startupfeedback
systembell
screentransform
kscreen

Currently Active Effects:
-------------------------
blur
contrast
glide
highlightwindow

Effect Settings:
----------------
shakecursor:

screenshot:

outputlocator:

colorpicker:

zoom:
zoomFactor: 1.2
mousePointer: 0
mouseTracking: 0
focusTrackingEnabled: false
textCaretTrackingEnabled: false
focusDelay: 350
moveFactor: 20
targetZoom: 1

screenedge:

blur:

contrast:

logout:
pluginId: logout
isActiveFullScreenEffect: false

login:
pluginId: login
isActiveFullScreenEffect: false

sessionquit:
pluginId: sessionquit
isActiveFullScreenEffect: false

slidingpopups:
slideInDuration: 200
slideOutDuration: 200

windowaperture:
pluginId: windowaperture
isActiveFullScreenEffect: false

translucency:
pluginId: translucency
isActiveFullScreenEffect: false

slide:
horizontalGap: 45
verticalGap: 20
slideBackground: true

glide:
duration: 160
inRotationEdge: Top
inRotationAngle: 3
inDistance: 30
inOpacity: 0.4
outRotationEdge: Bottom
outRotationAngle: 3
outDistance: 30
outOpacity: 0

fullscreen:
pluginId: fullscreen
isActiveFullScreenEffect: false

dimscreen:
pluginId: dimscreen
isActiveFullScreenEffect: false

frozenapp:
pluginId: frozenapp
isActiveFullScreenEffect: false

fadingpopups:
pluginId: fadingpopups
isActiveFullScreenEffect: false

squash:
pluginId: squash
isActiveFullScreenEffect: false

maximize:
pluginId: maximize
isActiveFullScreenEffect: false

sheet:
duration: 300

dialogparent:
pluginId: dialogparent
isActiveFullScreenEffect: false

windowview:
activeView: 
delegate: 
animationDuration: 300
ignoreMinimized: false
mode: 
partialActivationFactor: 0
gestureInProgress: false
searchText: 
selectedIds: 

tileseditor:
activeView: 
delegate: 
animationDuration: 200

overview:
activeView: 
delegate: 
animationDuration: 300
ignoreMinimized: false
filterWindows: true
organizedGrid: true
overviewPartialActivationFactor: 0
overviewGestureInProgress: false
transitionPartialActivationFactor: 0
transitionGestureInProgress: false
gridPartialActivationFactor: 0
gridGestureInProgress: false
desktopOffset: 
searchText: 

highlightwindow:

blendchanges:

startupfeedback:
type: 0

systembell:

screentransform:

kscreen:


Loaded Plugins:
---------------
BounceKeysPlugin
KeyNotificationPlugin
StickyKeysPlugin
buttonsrebind
eis
krunnerintegration
nightlight
screencast

Available Plugins:
------------------
BounceKeysPlugin
KeyNotificationPlugin
StickyKeysPlugin
buttonsrebind
eis
krunnerintegration
nightlight
screencast

ADDITIONAL INFORMATION
None to report. Themes should be in KWin Support Information if that matters.
Comment 1 krunkske 2025-04-25 18:18:46 UTC
Created attachment 180661 [details]
The Line in Konsole
Comment 2 John Kizer 2025-04-26 06:17:34 UTC
*** Bug 503357 has been marked as a duplicate of this bug. ***
Comment 3 Lenzoid 2025-05-01 17:04:30 UTC
I've asked around in the Bug Triaging Team, so far none of us has seen this or were able to reproduce it.

Could you go into detail how you reproduce the bug? Perhaps even make a screen recording of it.

Alternatively, what would be interesting:

- Is it reproducible with a more recent KDE? For example booted from KDE Neon Unstable version.
- Is it reproducible with a screen scaling of 100 or 125%?

Thanks in advance.
Comment 4 krunkske 2025-05-03 11:49:30 UTC
(In reply to Lenzoid from comment #3)
> I've asked around in the Bug Triaging Team, so far none of us has seen this
> or were able to reproduce it.
> 
> Could you go into detail how you reproduce the bug? Perhaps even make a
> screen recording of it.
> 
> Alternatively, what would be interesting:
> 
> - Is it reproducible with a more recent KDE? For example booted from KDE
> Neon Unstable version.
> - Is it reproducible with a screen scaling of 100 or 125%?
> 
> Thanks in advance.

Thanks for the quick response!
There aren't really any steps to reproduce this other than just opening kate or konsole on my system and tying a bit until the line is there. Although changing your screen scaling to 115% might help reproduce it. I will try KDE Neon later today to see if the issue is there too but I doubt it will.

Changing the screen scaling factor to 100% or 125% from my usual 115% makes the issue go away in both kate and konsole. There is also a small gap between the taskbar and some apps like discord that also dissapears with 100% scaling but not 125% but this seems to be an unrelated issue that I will report later.

Have a nice day!
Comment 5 krunkske 2025-05-03 12:13:40 UTC
The issue does not appear in KDE Neon Unstable with 115% scaling.
Comment 6 Lenzoid 2025-05-03 15:28:44 UTC
Thanks for all the new information!

Since it's likely been fixed already in Neon unstable it is safe to assume it will show up in the next major release. 6.4 is scheduled for release on Tue 2025-06-17 and if my experience with git-master as a daily driver applies here, it will bring a truckload of bug fixes. If you're satisfied we can close this for now and you could reopen it later if necessary.
Comment 7 krunkske 2025-05-03 16:43:56 UTC
(In reply to Lenzoid from comment #6)
> Thanks for all the new information!
> 
> Since it's likely been fixed already in Neon unstable it is safe to assume
> it will show up in the next major release. 6.4 is scheduled for release on
> Tue 2025-06-17 and if my experience with git-master as a daily driver
> applies here, it will bring a truckload of bug fixes. If you're satisfied we
> can close this for now and you could reopen it later if necessary.

Perfect!
In the meantime i'l just run at 110% scaling and wait a few weeks. Thanks for the help!