I'm not sure it's the same feature I tried to describe. I will get into details.
The "Hidden status flag" should be available into user profile setting, as a check box.
The online status of a user after the login should be not really hidden, just maskered from see who he is. That's because any online user must be counted into the user list comprofiler module, eg:
ONLINE USERS:
- user1
- user2
- user3
(and 2 hidden users)
In this example, module shows total 5 users online so any member presence is missed.
The hidden status should also affect CB userLists, where users with "hidden flag" set ON should be always "HIDDEN", even if online or offline.
Did you mean that, trail?