Error: 1 problem in 1 formula detected
ffmpeg:
* Non-executables were installed to "/usr/local/opt/ffmpeg/bin"
The offending files are:
/usr/local/opt/ffmpeg/bin/python
I believe the failure is the python binding to mpv when it's built/compiled. You could submit a bug report to mpv on GH.
Not our fault.
If ffmpeg 4.2 is installed, then mpv doesn’t work:

If mpv is reinstalled, then it doesn’t work either, because it wishes the old ffmpeg 4.1.4_1:

✓ fratti@archbook ~ $ /usr/bin/mpv --version
mpv 0.29.1 Copyright © 2000-2018 mpv/MPlayer/mplayer2 projects
built on Tue Aug 6 14:50:47 CEST 2019
ffmpeg library versions:
libavutil 56.31.100
libavcodec 58.54.100
libavformat 58.29.100
libswscale 5.5.100
libavfilter 7.57.100
libswresample 3.5.100
ffmpeg version: n4.2
Guess I'm a fucking wizard then.
This is homebrew's problem.
This is homebrew's problem.
Which a new release could solve. Please understand that I cannot make an official release of mpv.
@retokromer if you think making ABI bump releases is the upstream mpv project's duty, you're incredibly ignorant of how software packaging works.
@CounterPillow I’m just a Jew.
Excuse me, what?
In the mean time, as a workaround, you are free to use the mpv cask (from "brew cask install mpv"), which pulls from:
https://laboratory.stolendata.net/~djinn/mpv_osx which is referenced by https://mpv.io/installation
The cask doesn't rely on shared libraries, it uses its own internal ones.
In the mean time, as a workaround, you are free to use the mpv cask (from "brew cask install mpv")
Thank you, that’s useful indeed!
Most helpful comment
Guess I'm a fucking wizard then.
This is homebrew's problem.