There are a few particularly pernicious sites that I actually use who also monitor users activity everywhere online, mostly just Facebook, but every so often I'll log into a Google service.
I'll set up disjoint Firefox profiles for each such site and launch them with aliases or scripts, like facebook that accesses facebookcorewwwi.onion, or google that connects from tor to a vpn.
Ideally, these special profiles should fail to access sites not critical to their respective sites, i.e. if I click a facebook link to youtube then a tab opens with a 404 message and I manually copy the youtube URL to a Firefox instance with another profile.
Two questions:
- Does Firefox share any information between profiles? Caching, Site data, etc.?
- How would you go about ensuring a profile to only works on a specific site?
Any other considerations you can think of?