mod_roster_command: Fix subscription when the "user JID" is a bare domain. Do not attempt to update the roster when the user is bare domain (e.g. a component), since they don't have rosters and the attempt results in an error: $ prosodyctl mod_roster_command subscribe proxy.example.com contact@example.com xxxxxxxxxxFailed to execute command: Error: /usr/lib/prosody/core/rostermanager.lua:104: attempt to concatenate local 'username' (a nil value) stack traceback: /usr/lib/prosody/core/rostermanager.lua:104: in function 'load_roster' /usr/lib/prosody/core/rostermanager.lua:305: in function 'set_contact_pending_out' mod_roster_command.lua:44: in function 'subscribe'

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summary: Block s2s connections based on admin blocklists
...

This module uses the blocklists set by admins for blocking s2s
connections.

So if an admin blocks a bare domain using [Blocking Command][xep191]
via [mod\_blocklist][doc:modules:mod_blocklist] then no s2s connections
will be allowed to or from that domain.