← Your scroll listener fires on every pixel. `IntersectionObserver` fires when visibility actually changes.Quiz
IntersectionObserver: visibility without a scroll listener
IntersectionObserver reports visibility changes asynchronously instead of running on every scroll pixel. Know how threshold and rootMargin decide WHEN it fires, what an entry actually exposes, and how to stop watching once you're done.
questions6
pass mark70%
resultsat the end
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