fPI will isolate every first-party domain as much as the browser can, including HSTS and other security related properties. This means that if you visit exampl

fPI will isolate every first-party domain as much as the browser can, including HSTS and other security related properties. This means that if you visit example.com and then initech.com and both load a tracker from evilshit.org, then the tracker will see too completely fresh browser installs, not even HSTS will be setup if it was used. Basically, every domain you type into the URL address bar behaves as if it was a unique container.