[Wayland]Mouse pointer doesn't change to "resize" pointer when hovering over window borders with `--border=no`

mpv Information

mpv v0.41.0-388-g1301fdb2e Copyright © 2000-2026 mpv/MPlayer/mplayer2 projects
 built on Apr  7 2026 19:09:48
libplacebo version: v7.362.0 (v7.360.0-8-g4c654e50)
FFmpeg version: N-123859-ge7696357de
FFmpeg library versions:
   libavcodec      62.29.101
   libavdevice     62.4.100
   libavfilter     11.15.101
   libavformat     62.13.102
   libavutil       60.29.100
   libswresample   6.4.100
   libswscale      9.7.100

Other Information

- Linux version: Arch btw.
- Kernel Version: Yes
- GPU Model: Intel
- Mesa/GPU Driver Version: 26.0.4
- Window Manager and Version: KDE Plasma 6.6.4
- Source of mpv: Yes
- Latest known working version: Unknown
- Issue started after the following happened: Nothing has happened

Reproduction Steps

1. Hover mouse pointer over window border with --border=no

Expected Behavior

Mouse pointer changes to "resizing" one.

Note that it changes after clicking, but without visual indication it is hard to know where to click.

Actual Behavior

Mouse pointer doesn't change to "resizing" one.

Log File

No.

Sample Files

--idle

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

• I tested and confirmed that the issue exists with the latest release version or newer.
• 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 tracing mpv's Wayland window-border pointer handling with --border=no; the issue names no source file or test entry point. Reproduce with --idle by hovering the border, and consider the work complete when the pointer changes to the resizing cursor before clicking.