Frontend · Mid-level · Theory

Users complain that the page stutters and lags when they scroll. How would you look for the cause, and what role might reflow and repaint play here?

~4 min by voice

How to approach it

They're checking whether the candidate understands the browser's rendering pipeline (style -> layout -> paint -> composite) and can methodically find the bottleneck with DevTools instead of guessing. It's also important to know the typical causes of scroll jank and concrete ways to fix them.

Have you seen this question in a real interview?

Answers0

Avg. score—

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Practiced0

Topics

rendering performance

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Answer by voice

The interviewer will ask this question and listen. Think out loud and ask for a hint if you need one. When you're done, pause or tap “That's my answer”. In about a minute, your score and the points you covered show up here.

Best with headphones · ~4 min