Kiosk Watchdog

A user starts a transaction at the kiosk → gets redirected to an SSO / login page → realizes they don't have their phone for multi-factor auth → walks away. The browser sits on the login page until the next person walks up, who now sees a half-completed login session belonging to someone else. The watchdog detects "off the kiosk URL for too long" and silently sends the tab back home.