[X11] mpv reset window position

mpv Information

mpv v0.40.0 Copyright © 2000-2025 mpv/MPlayer/mplayer2 projects
libplacebo version: v7.349.0
FFmpeg version: 7.1.1-1+b1
FFmpeg library versions:
   libavcodec      61.19.101
   libavdevice     61.3.100
   libavfilter     10.4.100
   libavformat     61.7.100
   libavutil       59.39.100
   libswresample   5.3.100
   libswscale      8.3.100

Other Information

- Linux version: Debian unstable
- Kernel Version: 6.12.21-1
- GPU Model: Radeon RX 7600
- Mesa/GPU Driver Version: 25.0.2-1
- Window Manager and Version: Openbox 3.6.1
- Source of mpv: Debian repository
- Latest known working version: 0.39.0
- Issue started after the following happened: Play a media

Reproduction Steps

Set --geometry, move the window and play a media.

Expected Behavior

Keep mpv window position even when the --geometry option is used.

Actual Behavior

I set a position with --geometry, but if I move the window and play a media, the window go back to it's default position.
I tried --force-window-position but it's same.

The issue appears only if --geometry is used, does not happen on v0.39.0.

Log File

mpv --no-config --force-window --idle --geometry=+50%+50% --log-file=mpv_log.txt --gpu-debug
Then moved the window, played a FLAC file and exited mpv.

mpv_log.txt

Sample Files

No response

I carefully read all instruction and confirm that I did the following:

• I tested with the latest mpv version to validate that the issue is not already fixed.
• I provided all required information including system and mpv version.
• I produced the log file with the exact same set of files, parameters, and conditions used in "Reproduction Steps", with the addition of --log-file=output.txt.
• I produced the log file while the behaviors described in "Actual Behavior" were actively observed.
• I attached the full, untruncated log file.
• I attached the backtrace in the case of a crash.

Reproduce the regression with the provided mpv command, --geometry=+50%+50%, a moved window, and a FLAC file; review the attached mpv_log.txt. Trace the X11 window-position handling around playback and geometry updates. Done means a manually moved window keeps its position when media starts, while --geometry remains supported.