How do I turn on the Active Friends sidebar in Facebook?

There used to be a sidebar on the right side of the Facebook window that showed active and recently-active friends. Now it’s not there. I tried searching for help, finding a question asking how to see which friends are active. The answer was about how to send a friend a message, which wasn’t helpful (especially since it said to find the friend in the sidebar).

So how do I get this feature back?

Nevermind. I randomly clicked on Chat, and the list popped up.

Closed since the OP has found the answer.