It looks like it's related to a libav bug. See https://bugzilla.libav.org/show_bug.cgi?id=597 and https://bugzilla.libav.org/show_bug.cgi?id=341 It has been fixed in libav between versions 9.13 and 9.14.
So it looks like Firefox is less permissive than Gstreamer, Chromium and VLC on WebM files...
In any case, could Firefox output an error message in such cases, instead of silently failing?
It looks like it's related to a libav bug. See https:/ /bugzilla. libav.org/ show_bug. cgi?id= 597 and https:/ /bugzilla. libav.org/ show_bug. cgi?id= 341
It has been fixed in libav between versions 9.13 and 9.14.
So it looks like Firefox is less permissive than Gstreamer, Chromium and VLC on WebM files...
In any case, could Firefox output an error message in such cases, instead of silently failing?