ind.ie: @BarnabyWalters The videos should be working in Firefox (will test on nightly). If not, it’s a bug. Somewhat limited by Vimeo in formats.

@indie not working in FF 31 or Nightly 34.0a1 OS X 10.9.4 due to patent-encumbered encoding, screenshots:

See notes on https://developer.mozilla.org/en-US/docs/Web/HTML/Supported_media_formats#Browser_compatibility for more details

Vimeo actively blames users for using free software, do not recommend.