How to reproduce:
- create a new course
- open the course
=> in the toolbar the system reports that two users would be in the course.
It might be that this bug is only present when IM is enabled.
The problem probably that OLAT creates a chatroom for the course and adds a technical user to the chatroom which is necessary to administrate this chat room. This technical user is not visible in OLAT, it's only visible when using an external chat client. My guess is that this technical user is also counted in the GUI