Ok I'm pretty happy with this revision of the MediaWiki TimedMediaHandler video player dialog.
Check it out in action! https://video-testing.wmflabs.org/
Still some stuff todo, but it's a big step-up for the "beta mode" video player. Once it gets through review this'll land on Wikipedia, probably in a week or two. Next stab on it I'll make some improvements on audio handling and supporting embed/sharing.
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