Mozilla released security updates for Firefox 220.127.116.11 and Firefox 18.104.22.168 for Windows, Mac, and Linux.
The specific updates include some security fixes, meaning that it is strongly recommend that all Firefox users upgrade to these latest releases.
Users of Firefox 1.5.0.x or Firefox 2.0.0.x, will receive an automated update notification. This update can also be applied manually by selecting "Check for Updates..." from the Help menu at any time.
For a list of changes and more information, review the Firefox 22.214.171.124 Release Notes
and the Firefox 126.96.36.199 Release Notes