For some reason when I have the private chat tab open with someone for extended periods of time the following thing happens:
<00:54:33> Your chat partner has disconnected.
<10:12:17> Your chat partner has disconnected.

The user was not on the server from 00:54:33 onwards. However I got another notification that he disconnected again at 10:12:17 even though he was not on the server. Why is that?
Strangely enough, I was on two servers at the same time with this user. I also had a seperate private chat on both with this person. This happened only at one of the servers, on the other one the last message was that he disconnected at 00:54:33. Weird stuff.