How to check what version of Firefox installed?

It's often important to know what version of Firefox you are using, to help you troubleshoot a problem or just to know if Firefox is up to date. Here are two ways to find out:

Click the menu button , click help and select About Firefox.On the menu bar, click the Firefox menu and select About Firefox. The About Firefox window will appear. The version number is listed underneath the Firefox name.

Alternatively, click the menu button , click help and select Troubleshooting Information. A page with the address about:support will appear in a new tab. Your Firefox version is listed underneath the Application Basics section of the page.