Package: libvpx6 Version: 1.8.2-1 $ youtube-dl -f webm https://www.youtube.com/watch?v=ccclA2ZSwH8 $ chromium *.webm even the volume control is greyed out. But https://html5test says WebM with VP9 support Yes ✔ ffplay, mplayer also no sound. An vp8 version of the file on my disk from last year plays fine.