Browser & Web Performance · Middle · Question 18 of 75

What does `requestIdleCallback` do?

1Waits for the network to become idle
✓Correct answer: Runs a callback when the browser is idle, for low-priority background work
3Pauses all JavaScript until the user is idle

Explanation

It's good for things like sending analytics or prefetching. Don't use it for work the user is waiting to see.

Further reading

MDN: requestIdleCallback() ↗

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