mod_pubsub_serverinfo: Treat public providers as public The opt-in mechanism is to prevent leaking domain names or relationships between small private servers. These are not considerations relevant to public servers. We use the providers.xmpp.net API to fetch a list of known public provider domains.

This module discards typing notifications sent to a bare host JID,
preventing error replies to be sent. These errors are harmless but can
be annoying sometimes if your client shows them prominently.