OSC font varies randomly(?) if filename contains a character not in osd-font

[rivke41levp656]

mpv Information

mpv v0.39.0 Copyright © 2000-2024 mpv/MPlayer/mplayer2 projects
 built on Nov 27 2024 18:31:26
libplacebo version: v7.349.0
FFmpeg version: n7.1
FFmpeg library versions:
   libavcodec      61.19.100
   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

.

Reproduction Steps

Run mpv via e.g. mpv --no-config --include=mpv.conf --input-conf=input.conf -- あ.mkv. Repeatedly cycle the OSC, and the OSD font will change from what is set in mpv.conf (Liberation Mono, which probably contains only ASCII characters) to a fallback font (in my case Noto Sans CJK). If I rename あ.mkv to a.mkv, the problem does not seem to occur.

Example video of the bug where I repeatedly cycle the OSC, notice the OSD font changing:

bug.mp4

Expected Behavior

The OSD font should never change from what is set in mpv.conf.

Actual Behavior

The OSD font varies.

Log File

mpv.log

Sample Files

mpv_conf.txt

input_conf.txt

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.

[TheOneric]

Logs show Liberation Mono is first resolving to usr/share/fonts/OTF/PowerlineSymbols.otf, 0, PowerlineSymbols for you. sans-serif is also queried and resolves to DejaVu Sans, while actual LiberationMono (postscript name) and NotoSansCJKjp-Regular only get select later on as fallbacks for the initial PowerlineSymbols choice. Do you have any overrides or similar in your fontconfig config?

At some point NotoSansCJK gets selected as the first fallback instead of LiberationMono and since it already provides everything no further fonts are looked up. I’m not sure what causes the fallback order to change and this might also depend on what libass handles mpv retains between OSD cycles.
But either way, the main issue here is Liberation Mono not directly resolving to your desired font (works for me) which most likely is due to your local configuration. If you fix your setup the fallback order becomes irrelevant and this won't happen anymore.

[rivke41levp656]

I guess the problem is this file then?

/usr/share/fontconfig/conf.avail/10-powerline-symbols.conf

which contains an override for Liberation Mono.

It is created by the powerline-fonts package. I could just delete it, but it would reappear whenever that package updates.