Right click the video. It's probably Flash. Plays using Flash in Firefox on my m...

DCKing on June 19, 2014 | parent | context | favorite | on: Twitter's GIF hack

Right click the video. It's probably Flash. Plays using Flash in Firefox on my machine.

OS X is the last platform where Firefox doesn't support H.264. They're working on it, but it doesn't seem to be landing soon.