Request: make message indicator session and timeout based

[geckonapper]

The message indicator (the red dot) shows up for old unread messages. I don't want to see that. I only want to see the red dot for new messages that come in during the current session. And hitting Reload should refresh the session making the red dot go away until a new message comes in. Also, there should be a timeout (preferably configurable) so that, for example, after 30 minutes the red dot goes away until a new message comes in. Thanks