code: function getElmScrollRecursive(root) {
  	return Array.from(root.children).reduce((scrolls, elm) => {
  		const scroll = getScroll(elm);
  		if (scroll) {
  			scrolls.push(scroll);
  		}
  		return scrolls.concat(getElmScrollRecursive(elm));
  	}, []);
  }
docs: Create an array scroll positions from descending elements