Bug 507111

Summary: Horizontal Line Glitches every few seconds
Product: [Applications] kate Reporter: Rui Guilherme <guilhermecunha.rui>
Component: generalAssignee: KWrite Developers <kwrite-bugs-null>
Status: RESOLVED DUPLICATE    
Severity: normal CC: christoph, kde, waqar.17a
Priority: NOR    
Version First Reported In: unspecified   
Target Milestone: ---   
Platform: Arch Linux   
OS: Linux   
Latest Commit: Version Fixed In:
Sentry Crash Report:
Attachments: Kate with lines

Description Rui Guilherme 2025-07-16 12:23:11 UTC
Created attachment 183273 [details]
Kate with lines

SUMMARY
I believe that randomly (I don't remember changing it in the system) thin vertical lines started flashing on my screen, I noticed that it doesn't happen while playing games.

STEPS TO REPRODUCE
1. setting your monitor scale to 115%
2. open Kate and maximize it

OBSERVED RESULT
Vertical lines on window

EXPECTED RESULT
These vertical lines don't appear

Linux/KDE Plasma: 6.15.6-arch1-1 
KDE Plasma Version:  6.4.2
KDE Frameworks Version: 6.16.0
Qt Version: 6.9.1

ADDITIONAL INFORMATION
I noticed that the issue was caused by my monitor's scale. At 115% (which I didn't set myself), the issue occurs, but when I set it to 125% or 100%, the issue doesn't happen.
Comment 1 Rui Guilherme 2025-07-16 12:25:15 UTC
I couldn't put the video here showing all the details, I uploaded it to YouTube: https://youtu.be/hJMGbjIX0pE
Comment 2 Waqar Ahmed 2025-07-16 12:42:31 UTC
Seems like 115 is a favorite :D
Comment 3 Waqar Ahmed 2025-07-16 12:43:21 UTC

*** This bug has been marked as a duplicate of bug 504015 ***
Comment 4 Christoph Cullmann 2025-07-21 21:25:48 UTC
:) I still think any non-power of two fractional scalings are no good idea :) If somebody has a idea what to fix where, that is welcome.