Unsupported operating systems do not receive security updates, have known exploits and can be dangerous to use, which makes it difficult to maintain Firefox on those versions.Ĭan I still browse safely with Firefox on OS X 10.9, 10.10 or 10.11? Apple made the last security update applicable to OS X 10.11 available in July 2018. Why has Firefox ended support for OS X 10.9, 10.10 and 10.11 users?Īlthough Apple does not have a public policy governing security updates for older OS X releases, its practice is to support the most recent three releases.

Affected users will not receive any further security updates. This was done to provide security updates until the final Firefox 78 ESR update (version 78.15.0esr) was released on October 5, 2021. These users were moved to the Firefox Extended Support Release (ESR) channel by an application update.

Firefox Mac OS X 10.9, 10.10 and 10.11 users move to Extended Support Releaseįirefox version 78 was the last supported Firefox version for Mac users of OS X 10.9 Mavericks, OS X 10.10 Yosemite and OS X 10.11 El Capitan.