Browser & Web Performance · Middle · Question 64 of 75

What is the back/forward cache (bfcache)?

1A service worker that caches history
2The HTTP cache used for back navigations
✓Correct answer: The browser keeps a full snapshot of a page in memory so Back and Forward restore it instantly

Explanation

Restored pages keep their JS state. An unload listener is a common reason pages can't use bfcache.

Further reading

web.dev: Back/forward cache ↗

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