For example, thanks to this confinement, even if an attacker manages to exploit a security vulnerability in *Tor Browser*, they wouldn't be able to access all the content of your Persistent Storage.
Select the [[!img tor-circuit.png alt="Tor Circuit" class="symbolic" link="no"]] button in the address bar to show the relays in the Tor circuit that is used to connect to the website in the current tab.
The letterboxing feature of *Tor Browser* helps to prevent websites from identifying your browser based on the size of its window.Without letterboxing, websites could use the size of the browser window to track visitors or weaken your anonymity.