I don't know what iina is, but youtube-dl + mpv mentioned by Angeo34 does exactly that (stream videos without pre-downloading them). Youtube-dl just gets the st

I don't know what iina is, but youtube-dl + mpv mentioned by Angeo34 does exactly that (stream videos without pre-downloading them). Youtube-dl just gets the stream URL and mpv plays it. And it's easy to use, just: mpv https://www.youtube.com/watch?v=oHg5SJYRHA0