I've found other CFS groups on kbin.social and on a.gup.pe. Maybe they are a little bit more active.

• https://kbin.social/m/mecfs
• https://a.gup.pe/u/mecfs
• https://a.gup.pe/u/cfs
• https://a.gup.pe/u/mecfs_de (German and doesn't seem to have any activity)

Kbin.social seems to work well, but I don't see any content from a.gup.pe. I think it works differently from the Lemmy instances.