Great work!

For those that use youtube-dl or yt-dlp in mpv implicitly (i.e., by adding it to your shell $PATH instead of in your mpv.conf), to get this addon to work, you need to explicitly declare a ~/.config/mpv.conf config with

ytdl_path="/opt/bin/yt-dlp"
or
script-opts-add=ytdl_hook-ytdl_path="/opt/bin/yt-dlp"

(but replace "/opt/bin/yt-dlp" with the absolute path of your youtube-dl/yt-dlp binary)

https://github.com/mpv-player/mpv/issues/8665#issuecomment-916305625

works well with mpv player. gave it a four because some Telesur videos do not play. They have different aspect ratio. Example is https://www.youtube.com/watch?v=jbSED1r9W-Q. If I try to manually run mpv on the tmp file that it creates, mpv does not start.
I can download this video with youtube-dl in terminal and play it directly to mpv no problem.
Here is the output if I manually play the EXTM3U file from terminal.

$ mpv /tmp/mozilla_buster0/rqIjNeCd
Playing: /tmp/mozilla_buster0/rqIjNeCd
Playing: https://www.youtube.com/watch?v=jbSED1r9W-Q
Refusing to load potentially unsafe URL from a playlist.
Use --playlist=file or the --load-unsafe-playlists option to load it anyway.
Exiting... (Some errors happened)

If I directly play the http from file i get it works and I get

$ mpv https://www.youtube.com/watch?v=jbSED1r9W-Q
Playing: https://www.youtube.com/watch?v=jbSED1r9W-Q
[mkv] Unexpected end of file (no clusters found)
(+) Video --vid=1 (*) (vp9 1080x1080 29.970fps)
(+) Audio --aid=1 --alang=eng (*) 'DASH audio' (aac 2ch 44100Hz) (external)
AO: [pulse] 44100Hz stereo 2ch float
[ffmpeg/video] vp9: No support for codec vp9 profile 0.
[ffmpeg/video] vp9: Failed setup for format vaapi_vld: hwaccel initialisation returned error.
VO: [gpu] 1080x1080 yuv420p
AV: 00:00:06 / 00:01:22 (7%) A-V: 0.000 Cache: 57s+8MB
[ffmpeg] tls: Error decoding the received TLS packet.
Exiting... (Quit)

Elegant solution.

up:
Future request: white icon for dark themes. Like this — https://i.imgur.com/QtOn9Ze.png

up2:
To work with mpv:
1. Create a script with: mpv --playlist="$1"
2. Open the playlists through it: https://i.imgur.com/0klS12Z.png