The green button misdirection seems to be on numerous websites these days Phil.
Be very careful. There used to be a song long ago asking what's behind the Green Door. Now you know.
It is common these days to have lots of download buttons which only 1 is linked to the programme you want and even then I never do auto installs only custom ones so I can un-tick or choose not to install if there are 'extras' with it.
PUP stands for Potentially Unwanted Programmes - they aren't necessarily malicious but if you have not knowing installed them they have no right to be there.
I downloaded portable FS from Snapfiles yesterday with no problems and have just run Malwarebytes to make sure.
You can get Malwarebytes free but you need to un-tick the auto checked 'Trial' box on install.