Gajim automatically adds a groupchat to the roster
I'm not sure about the steps to reproduce, but I'll try to tell everything that was done.
I was online from 3 clients: 1 conversations and 2 Gajim and I was in a groupchat with all three clients. The groupchat is on a different server from the one where my account is.
The room gets destroyed by a third-party user and (if that matters) my server goes down for a minute.
When the server goes up, I get a new invite to this groupchat and accept it from one of Gajim instances. Then, I close that gajim instance.
After some time I get back to another Gajim instance and accept this invite once again, but Gajim reports that this isn't a name of a groupchat. After looking at the roster, I see that Gajim has added this groupchat to the roster.