On October 9, Mozilla released Firefox 56.0.1, which is notable in that it’s the first version that will automatically upgrade 32-bit Firefox to 64-bit Firefox. The 64-bit version has been available for a while, but Mozilla chose to hold off automatically upgrading 32-bit installs to 64-bit until now.

As usual, there was no announcement for Firefox 56.0.1 from Mozilla. Not even CERT helped here, since the new version doesn’t contain any security fixes. I learned about the new version when Firefox itself prompted me to upgrade on October 18, more than a week after the release.

On the positive side, the upgrade from 32- to 64-bit Firefox on my Windows 8.1 computer worked flawlessly. Somewhat oddly, the 64-bit version installed in the same directory as the 32-bit version: C:\Program Files (x86)\Mozilla Firefox. On 64-bit versions of Windows, 64-bit applications usually get installed in C:\Program Files. Regardless, I haven’t experienced any new problems or strange behaviour, and my old Firefox shortcuts still work. According to Mozilla, the 64-bit version of Firefox is demonstrably more stable and secure.

Firefox 56.0.1 includes a single bug fix, unrelated to security.