Just want to add that although peebee's system for moving files on shutdown to /root/Downloads with normal root:root permissions certainly works, it ONLY works for downloads, NOT uploads.....and the browser has to be closed before you can access them (unless you perform a manual move/chown.)
This is why I developed 'Spot2Root', because it's independent.....and you can move/change permissions of files in both directions, regardless of whether the browser is still running or not. Some may consider it a bit clunky, but it works for me, and probably others, too.
We all have different 'use-cases'. As Mike says, not all browsers that insist on "running-as-spot" actually respect those limitations. Experimentation usually highlights the culprits.
Mike.