GIFs in signature/avatar?

[Valeska 184]

I want to know if I can use GIFs in my signature and as my avatar? If I can use GIFs, are there certain size and duration limits to follow? Thanks!

[Kaneki 1,073]

I had a GIF in my avatar until my commission was done, and I didn't get into any trouble, so I assume it's okay.

Signature, I would guess not, but let's let a mod/admin answer that.