You can download this version now and start using it, OR, if you decide to wait, you only have until end of Dec 2016 to download this version as Mozilla will no longer make the Firefox ESR version available after Jan, 1 2017 and you'll be stuck without a supported web browser for OS X 10.6.8, earlier.

This Firefox ESR web browser will be updated for OS X 10.6-10.8 users until April 2017. 45.x which, while being an older version, is still being updated for SECURITY CODE ONLY and no more feature updates. There is the Mozilla Firefox ESR ( Extended Security Release) ver. 48 and use this for only as long as you wish or chance. You can choose to take your chances and update your Firefox version to the last compatible vers.

This version may no longer be secure and the version you are using now, vers. 48.0.2, last updated at the end of August 2016. The last full featured Firefox version for OS X Snow Leopard is ver. Mozilla Firefox is ending web browser support for OS X 10.6-10.8. I just need to finish doing things w old docs that require old SW, eg FileMaker 6! I also have a much later FileMaker & am moving my databases to it - but one of them requires compatibility w/ a truly ancient version of Windows at an organization I work for - major upgrade is coming but not yet. My hardware is OK at least to OS 10.10, maybe later.

Of course, I will move to a much later MacOS as soon as practical. Will FireFox try to actually install the upgrade? If so, does it have a way of recognizing that I don't meet System Requirements, so it stops the upgrade without damaging my FF 47.0.1? Is there some setting I need to apply? If it's a preference, I'd have to do it QUICK. Updates for Chrome for OS 10.6 stopped before the updates to FireFox. When I launch FireFox, it's trying to download FireFox! (Presumably a newer version of same, which won't work w/ my OS.) So I quit FireFox & am now working in Chrome. The last version of FireFox that works w/ creaky old Snow Leopard is 47.0.1, which I installed a few months ago. OK, I'm still on OS X 10.6 in order to maintain compatibility w/ some old sw (uses Rosetta, which Apple dropped w/ OS X 10.7).

Mozilla firefox for mac os x 10.6.8