How to find who turned off chat on Facebook

This is a method to find the friends who are online, but turned off chat . It's a app which provide this service.It's a facebook app.

Type in the Facebook search bar "Online Now" and go to the app.

Then you will see the friends who are online including who turned off chat as well.

You can see a "Grey" colour "half circle" in front of the name of the friends who are turned off chat and you can see a "Green" colour full circle in front of the names of your friends who are not turned off chat.