GIF support: display and playback

[netromdk]

It would be great with GIF support on Memmy. Right now, GIFs show up as "black" images so it might look like connectivity issues to users.

It should display the first frame as an image and play the GIF if clicked upon. Similar to what Apollo did. Maybe show like a play icon on top before clicking it. It would be even greater if they were treated as regular videos with playback, pause, and a progress bar. Auto-play could be a setting. It should be off by default, though.

Thanks for making this great app!

Btw this is in relation to the feature request on [email protected].