Display ist flickering if KWIN_DRM_NO_AMS is disabled and xfreerdp is used

[stollr]

• Linux distribution and its version: KDE neon 6.0 (based on Ubuntu 22.04)
• Linux kernel version: inux version 6.8.0-103044-tuxedo
• Xorg version (if used): Wayland is used
• Desktop environment in use: KDE Plasma

I don't know if this issue is a follow up of #459 but it depends on the KWIN_DRM_NO_AMS env variable.

In the past I had the same issue as described in #459 and setting KWIN_DRM_NO_AMS=1 solved it. After the latest update of displaylink package (with bundled evdi) I tried to disable the env variable and the origin issue was indeed fixed.

But now, I connect to my office computer with xfreerdp (the remote device is running xrdp) and have the following issue:
xfreerdp is running in fullscreen mode spanning over my notebook's and my external monitor, which is connected via usb-c over a usb-hub running displaylink. When I move the mouse cursor to the second screen, the notebook starts to flicker. The attached screencast shows my main screen where the flickering happens. When I move the cursor back to the first screen the flickering stops.

When I set KWIN_DRM_NO_AMS=1 again and relogin, the issue does not occur anmore.

Bildschirmaufnahme_20240925_091339.webm

freerdp is running with this command:

xfreerdp /multimon /f /network:broadband /u:cstoller.local /v:192.222.1.22 +home-drive /kbd:0x00000407 /kbd-lang:0x0407 /audio-mode:0 -wallpaper +window-drag +toggle-fullscreen

I am not sure if the source of the issue is evdi, freerdp or kde plasma. But maybe you have an idea. If you need any further information please let me know.