Locked Private Browsing in Safari
Private Browsing in Safari will now be much more private, with a new setting — on by default — that will require you to authenticate using Face ID or Touch ID before you can open your private browsing session.
Unlike most things that use Face ID authentication, this won’t happen automatically, either. You’ll need to specifically tap the “Unlock” button, so you won’t have to worry about whatever is in your private browsing session inadvertently showing up just because you happened to swipe at it while looking at your iPhone.
You can also now set Safari to use a different search engine while in private browsing mode.