How to upload? - Right now Lemmy.world (and other Lemmy Instances) don’t accept gifs uploads. Convert your gif or video file to webp or apng to upload (you can use some online and offline programs). The files (in webp) should be less than 20 seconds long or they will not work. Sometimes when uploading there’s a fail, try uploading the file again.
Please try to keep the files small. Also, if you can, donate to your lemmy instance.
How to see? - Gifs in ‘apng’ won’t play automatically in some instances in webview and you need to open the image in a new tab (they do in Voyager for example). Gifs in ‘webp’ format should play fine in webview and in most Lemmy apps.
I’m using Sync and this doesn’t animate at all in any view, including when tapped.