If you're already running Firefox, you should receive an automatic update notification. You can also manually check for updates by going to the Help menu and selecting "About Firefox."
Since this is a "point release" following the major Firefox 48 launch, it carries over the big improvements we saw earlier this month: firefox 48.0.2
August 2016 Current as of this review: Obsolete (but useful for legacy systems or testing) If you're already running Firefox, you should receive
– A capable browser in its day, but today it’s a security risk and compatibility nightmare . Keep it only for offline or very controlled legacy environments. If you're already running Firefox
Improved video performance for systems supporting SSE3 without hardware acceleration. System Requirements
Firefox 48 marked the final version supported for users on OS X 10.6 (Snow Leopard), 10.7 (Lion), and 10.8 (Mountain Lion). Why People Still Search for Firefox 48.0.2