Back/Forward Cache (bfcache)

The back/forward cache (or bfcache) is a browser optimization that enables instant navigations when a user clicks the back or forward buttons. It works by storing a complete, frozen snapshot of a page in memory—including its JavaScript state—when a user navigates away. If the user returns to that page via the back/forward buttons, the browser can restore it immediately from memory, providing one of the fastest possible page load experiences.