Firefox 53.0 and later requires Windows, 7, 8 (8.1), 10 to run.
Only other option to be able to use current Firefox versions is perhaps installing or dual booting with a Linux distro with a lighter desktop options like XFCE and not the heavier Gnome 3 or KDE.
If your Vista PC is using a old 32-bit CPU then your options are more limited, though there are still some Linux distros that still support 32-bit like Lubuntu and Xubuntu among other light options.
thats double pity - outdated windows and outdated browser. there is nothing we can do except you upgrade to windows 7 or higher, if you can collect all drivers for your machine!
The funny thing is you can still update Vista manually with the latest Server 2008 fixes using them from a wsusoffline download. Works still fine and if MS does not close that hole supported till 2020.
Don't really use Vista any longer but needed to test the latest SeaMonkey security backports from ESR60. Don't want to break XP and Vista in 2.49 until 2.57 is released.
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