I think I accidentally faced a problem of a chat message appearing
twice in ChatConversationPanel.
With the display of history in new chats enabled, when I receive a
chat message and there's still no ChatPanel opened for its respective
sender, the message will sometimes appear twice i.e. the ChatPanel
gets opened, the piece of chat history appears, the message appears in
gray as if it's been loaded from history and then it appears in black
as if it was just received (which it was).
In my current SIP Communicator session, I also see another received
chat message appearing twice after the history has been loaded and
I've sent a chat message. The duplicate message is the first received
message after loading the history in the ChatPanel, only one message
is before it and it's not received, it's sent by me.