mpv with --fullscreen=yes resizes to a 1x1 window on GNOME Wayland

mpv Information

mpv --version                                                                                     
mpv v0.40.0 Copyright © 2000-2025 mpv/MPlayer/mplayer2 projects
 built on Jan  1 1980 00:00:00
libplacebo version: v7.351.0
FFmpeg version: 7.1.1
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: NixOS 25.11 (Xantusia)
- Kernel Version: Linux terra 6.16.12 #1-NixOS SMP PREEMPT_DYNAMIC Sun Oct 12 11:01:05 UTC 2025 x86_64 GNU/Linux
- GPU Model: AMD 5800H integrated, NVIDIA 3070m dGPU
- Mesa/GPU Driver Version: OpenGL version string: 4.6 (Compatibility Profile) Mesa 25.2.4
- Window Manager and Version: GNOME 48
- Source of mpv: NixOS package with patched `libplacebo` pinned to https://github.com/haasn/libplacebo/commit/3662b1f5d5a721f31cbf6c0ad090ac2345834cab to fix https://github.com/haasn/libplacebo/issues/333
- Latest known working version: Unfortunately haven't kept track of when it started, been a few months at least.
- Issue started after the following happened: A GNOME or MPV update; don't have more specific indicators

Possibly related https://github.com/mpv-player/mpv/issues/16650, but at least sizing works fine over there. `f` keybind works to bring the window back.

Reproduction Steps

1. Use mpv with --no-config --fullscreen=yes on launch in this environment
2. Observe the logs (and screen) to see that mpv resizes itself to a 1x1 invisible and uncontrollable window in the top right of the screen.

Expected Behavior

The MPV window exits fullscreen but remains usable in a windowed style.

Actual Behavior

The window disappears from the screen. The only way to bring it back is by pressing f.

Log File

mpv --no-config ./Happy_Birthday_Anabelle_the_Raccoon.mp4 --gpu-debug --fullscreen=no --log-file=output-without-fullscreen.txt

output-without-fullscreen.txt

mpv --no-config ./Happy_Birthday_Anabelle_the_Raccoon.mp4 --gpu-debug --fullscreen=yes --log-file=output-with-fullscreen.txt

output-with-fullscreen.txt

Both logs have several switches from fullscreen to "windowed".

Sample Files

https://github.com/user-attachments/assets/62aa233c-bfb5-4638-bc25-35093a53de93

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.

Start by reproducing the issue with mpv --no-config --fullscreen=yes on GNOME Wayland and compare the attached fullscreen and non-fullscreen logs. Trace the fullscreen-to-windowed resize path; done means the window remains visible and usable instead of becoming 1x1, while the f key behavior still works.