Support for Twitter

[simonlindholm]

Twitter uses their own custom form of GIFVs rather than true gifs. The videos can be detected by class="animated-gif", but some custom code is probably also needed to play nice with twitter's play-when-scrolled-into-view UI.

(MP4 needs to be enabled, otherwise it falls back to Flash which is harder to control. As a note to self the prefs needed for this are media.gstreamer.enable-blacklist;false, media.fragmented-mp4.exposed;true, media.fragmented-mp4.gmp.enabled;true).

[simonlindholm]

http://simonsoftware.se/temp/toggle-gifs.xpi is an (unsigned, so will stop working soon :( ) XPI with the above commit. It's slightly buggy but might be useful still.

Solving this fully seems like relatively low priority, because it's quite a bit of work, not that much value in it, and fragile because of possible Twitter changes. I'll think more about what to do the next time I poke at this addon.

[Geobert]

That's why it's not working in tweetdeck I guess :( why did they do such a thing? :'(