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 lets you block connections to remote servers at the s2s
level.

``` {.lua}
modules_enabled = {
    -- other modules --
    "s2s_blacklist",

}
s2s_blacklist = {
    "proxy.eu.jabber.org",
}
```