Bug 515122 - KWin Wayland 6.5.x sometimes initializes wrong color/sharpness on external monitor; fixed by kwin_wayland --replace
Summary: KWin Wayland 6.5.x sometimes initializes wrong color/sharpness on external mo...
Status: REPORTED
Alias: None
Product: kwin
Classification: Plasma
Component: general (other bugs)
Version First Reported In: 6.5.5
Platform: EndeavourOS Linux
: NOR normal
Target Milestone: ---
Assignee: KWin default assignee
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2026-01-26 17:37 UTC by rxr
Modified: 2026-01-27 09:38 UTC (History)
2 users (show)

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Description rxr 2026-01-26 17:37:53 UTC 
On Plasma 6.5.5 (Wayland), external monitors connected via DisplayPort sometimes initialize with incorrect color/sharpness after login.

Symptoms:
- Colors appear over-saturated / HDR-like
- Text looks extremely sharp or over-processed
- Gamma, brightness, and color settings have no effect
- Issue occurs non-deterministically (sometimes fixed after reboot)

Running:
  kwin_wayland --replace &

immediately fixes the issue without logging out, suggesting a KWin Wayland initialization bug in the color/scaling pipeline.

Environment:
- Plasma: 6.x
- KWin: 6.5.5
- Session: Wayland
- External monitor via DisplayPort
- Distribution: EndeavourOS (Arch-based)

The issue does not occur when using Plasma (X11).