Thumbnail not work on MacOS

[nvcken]

MacOS 10.14.4
mpv 0.32.0

Install MPV via brew cask (support added to Applications ) brew cask install mpv
I added these lines intro /Applications/mpv.app/Contents/Resources/mpv.conf

player-operation-mode=pseudo-gui
osc=no
load-scripts=yes

Copied 2 files mpv_thumbnail_script_client_osc.lua mpv_thumbnail_script_server.lua to ~/.config/mpv/scripts/
Open MPV to try thumbnail on seek bar but not work.
Please what I went wrong ?

[nvcken]

Change to this then it works, but don't know why only work with ffmpeg instead of mpv built-in, How can I open console detail ?
prefer_mpv=no

[paulrudy]

This is the same for me. prefer_mpv=no seems to be required in mpv_thumbnail_script.conf. Both ffmpeg and mpv are in PATH.

[SemperPeritus]

mpv installed by brew install mpv --cask can't generate thumbnails if open from Finder (Thumbnailing failed, check console details). But if I open file from terminal, everything works fine.
@nvcken Probably, you are right. Something wrong with PATH or virtual environment. I'm not sure how brew works, but I suppose it's similar to pip or may be even docker in Linux. I'm new in Mac OS world, so I'm not sure.
I will check the details in the next few days and write here.

[SemperPeritus]

After changing prefer_mpv to false I got the error that ffmpeg can't be found. After adding /opt/homebrew/bin to the path variable in server script I got the new error. Thumbnails still does not generates. whoami and touch launched from subprocess works fine. I have all permissions in "thumbnails folders" and have ffmpeg in the path variable. But it returns status -3 with empty stdout event after changing the loglevel. I run the same command from logs in command line and it works fine. So, probably it is a problem with brew dependencies installed by cask. All other subprocesses runs fine from mpv launched from Finder.

[SemperPeritus]

Solution, a little dirty:
Change ffmpeg and/or mpv in the ...server file to /opt/homebrew/bin/ffmpeg and/or /opt/homebrew/bin/mpv.