These users will be 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 is 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.