polyfill-service/polyfills/IntersectionObserverEntry/polyfill.js

A polyfill combinator

// Minimal polyfill for Edge 15's lack of `isIntersecting`
// See: https://github.com/WICG/IntersectionObserver/issues/211
Object.defineProperty(IntersectionObserverEntry.prototype,
	'isIntersecting', {
		get: function () {
			return this.intersectionRatio > 0;
		}
	}
);