Commit treason. It supports H.264, VP8, VP9 and AV1.
NOTE one does not simply commit treason on anything other than AMD64 or 386. No videos for Raspi users, sorry. You can still play audio only on other arches though.
nvi -A 251 -a /fd/1 ybGOT4d2Hs8 | mcfs -t audio | audio/opusdec > /dev/audio
The easiest way to play ANY video on Youtube is to use H.264 "baseline" stream. It's of pretty bad quality image-wise, but contains audio in the container itself and doesn't require too much CPU resources.
nvi -V 18 -v /tmp/vid.mp4 ybGOT4d2Hs8 && treason /tmp/vid.mp4 && rm /tmp/vid.mp4
If you want to find the best possible format(s), use the following:
nvi -a /tmp/audio -v /tmp/video ybGOT4d2Hs8 && treason -a /tmp/audio /tmp/video && rm /tmp/audio /tmp/video
You can put that script to
$home/bin/rc/youtube and add a plumb rule
for Youtube URLs, right before
type is text data matches 'https://(www.)?youtube[^ ]+' plumb start window youtube ''''$0''''
No. It's great.