One of my must have. It makes browser so much private by isolating every websites inside their own temporary container. Just remember to not accept third party cookies. After leaving site all cookies are deleted, but you still keep your history. If you want to keep cookies from one site (eg. to keep logged in), just create persistent (normal) container for this one site and check to always open this one site in its own container. It still gonna be isolated, but cookies won't be deleted.