Firefox 17 comes with a new Social API feature that can integrate your Facebook into the browser sidebar. That means, if you are logged into your Facebook account, you will be able to see your friends, your news feeds, receive notification and chat with your friends using the Facebook Messenger. Here is how you turn it on:
1. Make sure you are running Firefox 17. You can check your version of Firefox in the “About Firefox” section.
2. In your Firefox browser, go to this link: https://www.facebook.com/about/messenger-for-firefox. Click the “Turn On” button (You will have to login to your Facebook account).
That’s it. You should see a few Facebook icons appearing at your menu bar and the sidebar will appear with your Facebook friends.
Turning the Facebook messenger off
To turn it off, simply click the “Facebook” icon and select “Remove from Firefox”.