Facebook Messenger for Firefox: What Happened and How to Chat Today

Facebook Messenger for Firefox was a sidebar that let you chat with Facebook friends and see notifications while you browsed other sites. I turned it on the week it launched in December 2012. This guide explains what it was, why you can’t turn it on anymore, and the easiest ways to use Messenger in Firefox today.

Quick answer: The Facebook Messenger for Firefox sidebar no longer exists. It was built on Firefox’s Social API, which Mozilla later removed, so there is no “Turn On” button anymore. Today you can chat by opening Facebook’s messages page in a pinned Firefox tab, or by using the Messenger app on your phone.

What Facebook Messenger for Firefox was

In late 2012 Mozilla partnered with Facebook to launch Facebook Messenger for Firefox. It was the first service built on the new Firefox Social API. Once you turned it on, a sidebar on the right of the browser showed your Facebook friends and chats, so you could reply to messages without opening Facebook in a separate tab or window.

Your Facebook notifications, friend requests and messages also appeared as small icons in the Firefox toolbar. It was a handy way to stay connected while browsing (and, honestly, a handy way to get distracted from real work too).

How you turned it on

You visited the Facebook Messenger for Firefox page and clicked “Turn On”. You needed the latest version of Firefox, and you had to be logged in to Facebook. You could hide the sidebar with a single click and keep only the toolbar buttons, or switch the whole feature off.

What happened to it

The sidebar depended on Firefox’s Social API. Mozilla deprecated and later removed that API, and with it went the Facebook Messenger sidebar. If you search for the old “Turn On” page today, you won’t find a working version, and no official Firefox add-on replaced it.

Facebook’s own desktop options have also shrunk. Meta discontinued its standalone Messenger desktop apps for Windows and Mac, and in April 2026 it stopped supporting messaging on the separate Messenger.com website, sending visitors to Facebook’s messages page instead. The Messenger mobile apps for Android and iPhone still work.

How to use Facebook Messenger in Firefox today

You can still get a sidebar-like experience in Firefox with a few simple steps:

1. Open Facebook messages. Log in to Facebook (external site) in Firefox and open your chats from the Messenger icon at the top right.
2. Pin the tab. Right-click the tab and choose Pin Tab. It shrinks to a small icon at the left of the tab bar and stays there every time you open Firefox.
3. Allow notifications. When Facebook asks to show notifications, allow them so new messages pop up even when you are on another tab.
4. Keep Firefox updated. Get the latest version of Firefox (external site) so Facebook’s web chat works properly.

Other ways to chat while you browse

• Messenger on your phone: the Messenger (external site) app for Android and iPhone is now Meta’s main dedicated chat app.
• Facebook Container: if you worry about Facebook tracking you across sites, Mozilla’s Facebook Container (external site) add-on keeps your Facebook login in its own isolated tab.
• Other messengers: if your friends use WhatsApp, you can chat from the browser too. See how to use WhatsApp Web on a laptop or PC.

Looking for more social tools inside the browser? We have a list of the best Firefox extensions for social media.

FAQ

Can I still turn on Facebook Messenger for Firefox?

No. The sidebar was built on the Firefox Social API, which Mozilla removed. There is no official replacement, so use Facebook’s messages page in a pinned tab instead.

Is there a Messenger desktop app for Windows or Mac?

Meta has discontinued its standalone Messenger desktop apps. On a computer, use Facebook in your web browser.

Does Messenger.com still work?

Meta stopped supporting messaging on Messenger.com in April 2026 and sends visitors to Facebook’s messages page. Your chats are still available through Facebook and the mobile app.

Are old add-ons that promise a Messenger sidebar safe?

Be careful. Unofficial add-ons can ask for access to all your browsing data. Only install extensions from addons.mozilla.org with good reviews, and never enter your Facebook password into a third-party add-on.