This is cycon: CONnect to CYtube. If you just want to see the queue
of a CyTube [0][1] site, updated in real-time without a full web
browser, and maybe pipe a few of the URIs to an external media
player like mpv, this program may work for you.

You need:

 - libcurl
 - libwebsockets
 - yajl
 - unibilium

Note: Sometimes mpv takes a while to load. This can make the user
wonder “Did I really press that button? Is $DISPLAY set correctly?”.
Therefore, cycon doesn't launch mpv exactly; it assumes you have a
binary called ‘mpv-with-load-screen’ that will start immediately
(mine just prepends a 1x1 PNG file to the input arguments). See
launch.c.

[0] https://cytu.be
[1] https://github.com/calzoneman/sync