Intersection Observer comes to Firefox – Mozilla Hacks - the Web developer blog

What do infinite scrolling, lazy loading, and online advertisements all have in common? They need to know about—and react to—the visibility of elements on a page! Unfortunately, knowing whether or not an element is visible has traditionally been difficult on the Web. Most solutions listen for scroll and resize events, then use DOM APIs like getBoundingClientRect() to manually calculate where eleme

[Rockridge]

Intersection Observer APIはFirefox 55/Edge 15/Chrome 51以降でデフォルト有効化されている。要素が可視領域内にあるかどうかを判別できるため、広告コンテンツは本体動作に負荷のかかる独自の判別方法を採用する必要がなくなる。

[efcl]

Intersection ObserverがFirefoxに追加された

[manaten]

色んな場面でほしいやつだ

[koba04]

🎉