The OGG container format is currently under consideration https://dev.modern.ie/platform/status/oggcontainerIvan Privaci commented
Kind of crucial for web audio support (.ogg [vorbis] and .opus are both ogg containers)
Skipping ogg for video support is probably not so bad, but "webm" seems to be very video-centric. vorbis and opus audio on the web seems to be all ogg format.
I'm confident Xiph would be happy to help if you are having trouble implementing the format.
Opus is now in preview builds behind a flag. Please see https://blogs.windows.com/msedgedev/2016/04/18/webm-vp9-and-opus-support-in-microsoft-edge/Ivan Privaci commented
This is excellent news, and will make legally-free top-quality audio available on around 90% of web-browsers, I believe.
I wonder about this though: http://dev.modern.ie/platform/status/oggcontainer/
It says low priority and no development. ".opus" is opus-in-ogg. What's the plan here? "WebM Audio" (which I've never encountered "in the wild" except for a single test file I made myself)?
(Personally, I *much* prefer ogg's more flexible and simple metadata - webm has the same "70 or so special little differently formatted binary fields" limitation going on that mp3's "IDv2" does. I think .ogg is hypothetically better for streaming, too, but I'm not certain about that.)