64-Bit Firefox Is Now Available for Windows With Improved Performance
Windows: Firefox has been available in unofficial and test 64-bit builds for many years, but this week Mozilla finally released the official 64-bit version of Firefox for Windows 7 and up.
Along with other minor changes in Firefox 43, you’ll also find new versions of Firefox on the download page (you’ll have to re-download it from Mozilla; the update won’t give you the 64-bit version). Note that it does not support many plugins because Firefox is phasing out support for NPAPI plugins by the end of 2016, so if you still rely on any of them, you can stick with the 32-bit version for now. But if you are using a 64-bit system, you may see some performance improvements with the new version.
Check it out by downloading the installer here .
Firefox 64-bit for Windows is available | Future releases of Mozilla