Bug 509046

Summary:	xfreerdp "multimon" option gives corrupted visuals when direct scanout is enabled in Plasma Wayland
Product:	[Plasma] kwin	Reporter:	ottersaregrt
Component:	xwayland	Assignee:	KWin default assignee <kwin-bugs-null>
Status:	REPORTED ---
Severity:	normal
Priority:	NOR
Version First Reported In:	6.4.4
Target Milestone:	---
Platform:	Arch Linux
OS:	Linux
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:

Description ottersaregrt 2025-09-03 01:01:15 UTC

SUMMARY
Using the "multimon" option in xfreerdp results in flickering and corrupted visuals. However, disabling direct scanout by adding KWIN_DRM_NO_DIRECT_SCANOUT=1 to environment variables fixes this issue.

This seems dependent on the monitors used. A setup with two 4k monitors and QHD ultrawide results in this bug appearing, but another setup using a QHD ultrawide and a normal QHD monitor works without needing to disable direct scanout.

Bug report in xfreerdp: https://github.com/FreeRDP/FreeRDP/issues/10098

STEPS TO REPRODUCE
1. Connect to a xfreerdp session using /multimon with multiple monitors

OBSERVED RESULT
Visuals appear to flicker and are corrupted on each monitor as the mouse is moved.

EXPECTED RESULT
Visuals should not be corrupted.

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: Arch 6.16.4
KDE Plasma Version: 6.4.4
KDE Frameworks Version: 6.17.0
Qt Version: 6.9.1

ADDITIONAL INFORMATION