There is still another bug. We do not see the online status of the current user in the TitleBar when we sign in. This 
bug does not show, when we are already signed in and refresh the browser.

I need the full modification

I think we just need to call the update the online status of the current user in Redux at the sign in function, which 
should not be more than a line modification. What do you think?

The code is working but not perfect. I am online first for a split second then I am going back offline and stay like 
that. I see PUT request 3 times, at first it puts me offline then online 2x. The problem is that the currentUser do 
not follow this, because the currentUserSlice is not getting updated by SignalR.

The problem is solved, but enough to change the fakebook.users.put listener, because me won't get generated again.