Same problem over here too. If it's any consolation, I've been able to resolve the static comment image upload problem (via 'upload image' icon in formatting bar, which simply does not work sometimes for unknown reasons) with a simple ctrl-v? Not possible for GIFs, but I'll drop back in if I figure that out.
Edit: One successful GIF upload since this comment. Used 'upload image' on small file size & it worked like a charm. I'm wondering if there's a sort of file size ceiling which thwarted previous attempts?