While it has been known for a number of years that Mozilla planned to drop support for Windows XP from its Firefox browser, it made sense for that to occur sometime after Microsoft officially ended support for the aging operating system. Now, almost two years after Microsoft pulled the plug on Windows XP, Mozilla has clarified its intentions for ongoing support.
Commencing from around March 2017, Firefox users on Windows XP and Vista will be moved on to the 'Extended Support Release' cycle, normally leveraged by corporations and educational institutions requiring extended support for large-scale deployments. The change will occur automatically as part of the standard update process.
Users stuck on these older operating systems will still have time to consider their options, with Mozilla also announcing that it currently expects to "continue to provide security updates for users until September 2017." Despite a formal assessment of user telemetry slated to occur "in mid-2017" the browser developer has suggested that enterprises using its browser should anticipate that September 2017 will mark the end of Firefox support for these operating systems.
While Firefox will continue to work on Windows XP and Vista after the official end of support, the browser will become increasingly vulnerable to security flaws which remain unpatched. To this end, Mozilla has recommended that users "upgrade to a version of Windows that is supported by Microsoft."