>>338113804
You can still use the last version of favcat that avatar favorites worked with for now which is the one from 2021-05-04, idk how long it's going to keep working though and as far as I'm aware no one has expressed interest in forking the code and maintaining it or doing their own shit. I've been shitposting about it since the announcement and have gotten no useful replies.
https://github.com/knah/VRCMods/releases/tag/updates-2021-05-04