MUC presence on leave misses <item/>
Biboumi misses the <item/> in unavailable presences emitted when a participant leaves a MUC:
<presence type='unavailable' to='me@my.domain.example/resource' from='#channel%server@irc.my.biboumi.example/nickname'>
<status>Quit: http://www.kiwiirc.com/ - A hand crafted IRC client</status>
<x xmlns='http://jabber.org/protocol/muc#user'/>
</presence>Standards Reference: XEP-0045 §16.3
In order to inform occupants of room roles and affiliations, and to make it easier for clients to track the current state of all users in the room, MUC service implementations MUST provide role and affiliation data (and, if allowed by the room configuration, full JID) in all presence stanzas, including presence stanzas of type "unavailable" sent when a user exits the room for any reason.
(see also Example 82)
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