There are some communities that don't show up in the suggestion lower bar when typing. As a result, if I try to post in, say, anime @ ani.social via a "share" link on android, I can't continue because there's no community to tap on in the suggestion field.

It would be nice if you could attempt to post manually in a community manually typed in if it appears to be a community@site.domain format and wait for a post timeout before giving the warning that an invalid community is selected.

Unless I'm missing something, of course, that's always a possibility.