SUMMARY
Scale over 125% there is a 1px line on the bottom and right side of the screen that doesnt refresh if only part of scrren changes.

On screen scale 120% or below this is not happening.

STEPS TO REPRODUCE
1.  Set screen scale to 140%
2.  Put a auto hiding dock on bottom or activate screen corner for bottom left/right (or play a video on fullscreen)

OBSERVED RESULT
In case of auto hiding dock let it hide and move mouse down to get the highlight, move the mouse away, a line with the higlight color stays. Or using screen edges, move the mouse near the edge to trigger the color higlighting, move the mouse away and a 1px line stays there. Or if video, let it play for a few seconds and observe the bottom and right edge.

Triggering a virtual desktop switch/scroll or something that refreshes all the screen clears it to normal until next event.

EXPECTED RESULT

No pixel left overs

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: openSuse Tumbleweed
(available in About System)
KDE Plasma Version: 6.0.3
KDE Frameworks Version: 6.0.0
Qt Version: 6.6.3

ADDITIONAL INFORMATION
I tried to make a sceen capture but the problem isn't captured only visible on screen. Feels like the pixel line above the last one is duplicated below and not refreshed.

Screen resolution: 2560x1440
Scale: 140%

Sorry if maybe this is assigned to the wrong product and component