mpv installs an app that doesn't open

[ryandesign (Ryan Carsten Schmidt)]

mpv @0.34.1 installs an application bundle mpv.app but when I open it, its icon briefly appears in the Dock and then disappears again.

Running the binary on the command line shows that it doesn't appear to be a macOS application at all but rather just a command line program:

$ /Applications/MacPorts/mpv.app/Contents/MacOS/mpv
mpv 0.34.1 Copyright © 2000-2021 mpv/MPlayer/mplayer2 projects
 built on Wed Feb 23 15:32:43 CST 2022
FFmpeg library versions:
   libavutil       56.70.100
   libavcodec      58.134.100
   libavformat     58.76.100
   libswscale      5.9.100
   libavfilter     7.110.100
   libswresample   3.9.100
FFmpeg version: 4.4.1

Usage:   mpv [options] [url|path/]filename

Basic options:
 --start=<time>    seek to given (percent, seconds, or hh:mm:ss) position
 --no-audio        do not play sound
 --no-video        do not play video
 --fs              fullscreen playback
 --sub-file=<file> specify subtitle file to use
 --playlist=<file> specify playlist file

 --list-options    list all mpv options
 --h=<string>      print options which contain the given string in their name

$

This is on Mac OS X 10.7.