You can still run 32-bit applications like 32-bit Firefox on 64-bit Windows. Otherwise, we'd probably all need to throw away a lot of our software...

64-bit Firefox has the advantage of being able to use more memory, which could be useful if you have 8 GB.

64-bit Firefox has the disadvantage that the only plugins you can run are Flash and Silverlight (and Silverlight only in your current ESR series, not in later versions).

townerh said

I'm unsure of whether or not I need to match my 64 bit OS with a 64 bit Firefox.

Win64 Firefox has existed for Release since version 42.0 and it has required 64-bit Windows 7, 8 (8.1), 10. Even if you have 64-bit WinXP or Vista you can still only run 32-bit Firefox.

https://www.mozilla.org/firefox/52.6.0/system-requirements/

Thanks for the help! May your day be blessed!