mod_bookmarks2: Advertise XEP-0049 support In the case mod_private isn’t loaded, some clients (like poezio) won’t even attempt to use Private XML Storage unless this feature is advertised. This is on the domain JID and not on the account JID!

This module lets you block connections to any remote servers not on a
whitelist.

``` {.lua}
s2s_whitelist = {
    "example.org",
}
```