Image flickering in fullscreen mode

Important Information

• mpv version: 0.34.0
• Linux Distribution and Version: Fedora Linux 35 KDE Plasma
• Source of the mpv binary: rpmfusion-free
• If known which version of mpv introduced the problem: unknown
• Window Manager and version: kwin 5.23.4
• GPU driver and version: NVIDIA 495.46
  G-SYNC Compatible is enabled in the NVIDIA settings

Reproduction steps

The issue is reproducible with the option --no-config after switching to fullscreen mode.
The issue is not present when using the option --vo=vdpau,xv
The issue is not present when G-SYNC Compatible is disabled and "Force Composition Pipeline" is enabled

Expected behavior

No flickering is seen in the fullscreen mode.

Actual behavior

Flickering of the image is seen also when the video is paused. The flickering looks like a slight change of brightness.
It gets more visible when moving the cursor in the fullscreen mode.

Log file

Log file made with mpv --no-config -v --log-file=output.txt sample.mkv: https://0x0.st/o-BS.txt

Start by reproducing fullscreen playback with mpv --no-config and the provided sample.mkv, using the linked verbose log as the initial evidence. Compare the default video output with --vo=vdpau,xv and the documented G-SYNC/Force Composition Pipeline settings. Done means fullscreen playback, including paused video and cursor movement, shows no brightness flicker.