Browser & Web Performance · Middle · Question 65 of 75

How can a page detect that it was restored from bfcache?

1performance.now() is reset to 0
✓Correct answer: In a pageshow event, event.persisted is true
3DOMContentLoaded fires a second time

Explanation

Use it to refresh stale data (e.g. cart contents). Use pagehide instead of unload for cleanup.

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