It appears that mine is not functioning that way. When I click the "Friends" icon, it pops up the list of friends and shows my one friend (me, on another computer) online. It shows the profile image with the yellow "online" indicator, and also shows the username (which, incidentally, I would like to change to their full name... is that possible?). It also shows the "Friend Requests" and "Online Friends" links.
when I click on the friend's icon, it simply takes me to their profile page; it does not prompt me to start a chat with them.
Any ideas? Maybe I missed a setting somewhere?
you can see how many friends you have online from the friends icon in the bottom bar. If you click on it, it will show you which friends are online. Then all you have to do is select a friend and opt to chat to them. This will open up the messenger.
Hope this helps,
Nathan