https://lemmyrs.org/c/[email protected] works for me. I believe there is a generic way to link to communities that works for all sites.. but I don't know how. I know the format is something like [email protected] but nothing seems to convert to a link etc
Edit: perhaps just relative links? /c/[email protected]
Odd. I can click the relative link in Connect but it errors with "Could not find a user with that id" and gives me a blank/nulled view. The search in conncect is also pretty broke imo and while I can find kbin.social things, the rust one doesn't even show up for a pretty explicit search.
Not an instance issue at least. Opening over the website and subbing from there worked. Lemmy apps seem to still have a long way to go.
Edit: Btw, I read some post about using lemmy and that relative link is the way to go.