`inView` is fired too many times.

[flinnb]

W should really only fire inView when the item actually scrolls into view, not on every scroll where the element is visible.

[YurySolovyov]

https://developer.mozilla.org/en-US/docs/Web/API/Intersection_Observer_API + polyfill https://github.com/WICG/IntersectionObserver/tree/gh-pages/polyfill#browser-support