Today, this community browser shows me only 0 results. I tried with different browsers + in-private sessions, but I do not get anything anymore :-(

If you have trouble joining one of their communities, search for the link to the community, then your server will look it up. (search for the link, like this: https://beehaw.org/c/chat).

If that still doesn’t work, make sure that the server that the community is on isn’t banned by your server. You can check by clicking on Instances in the very bottom of the web UI.