While reviewing XEP-0186 just now, I noticed that when a resource goes invisible, its server must send presence of type unavailable from that resource. As far as I can see, when a contact's server receives unavailable presence from the user (and if the user+contact have a two-way presence subscription), it will stop sending presence updates to the user (if that was the last online resource for the user). This somewhat defeats the purpose of invisibility, no? The implication is that the user's information about the presence of its contacts will soon become stale. But I suppose that's one price you pay for invisibility, which I continue to think is a stupid concept anyway. :)
Peter -- Peter Saint-Andre https://stpeter.im/
