Will it run on Windows XP-Pro?
Sorry, no: https://docs.floorp.app/en/introduction/installation/.
Firefox version 52.9. 0 ESR was the last supported release for Windows XP and Windows Vista
Firefox ESR https://archive.org/details/firefoxsetup52.9.0esrenus
In which the legacy extensions work, thank God. I still have it though not being used,
Will it run on Windows XP-Pro?
XP has been past EOL for ten years next month.
Time to give it up.
https://floorp.app/en/download/
XP is a 32 bit OS
There’s a Windows 32 bit version and a Windows Portable version.
One of these might work