Board Thread:Support Requests - Designing Your Wikia/@comment-27048378-20160927053538/@comment-3508553-20160927190558

While I doubt that you can do it wiki/fandom/wide, you can do it on your home wiki (if you're admin or if you beg someone else) to pull the ID for your userpage and replace your avatar with a gif via CSS.

To be noted, transparent backgrounds are not even supported by Wikia/Fandom.