https://shop.dailymaverick.co.za/wp-content/themes/storefront/assets/js/woocommerce/header-cart.js?ver=4.6.1

1/**
2 * Makes the header cart content scrollable if the height of the dropdown exceeds the window height.
3 * Mouseover is used as items can be added to the cart via ajax and we'll need to recheck.
4 */
5( function () {
6	if (
7		document.body.classList.contains( 'woocommerce-cart' ) ||
8		document.body.classList.contains( 'woocommerce-checkout' ) ||
9		window.innerWidth < 768 ||
10		! document.getElementById( 'site-header-cart' )
11	) {
12		return;
13	}
14
15	window.addEventListener( 'load', function () {
16		const cart = document.querySelector( '.site-header-cart' );
17
18		cart.addEventListener( 'mouseover', function () {
19			const windowHeight = window.outerHeight,
20				cartBottomPos =
21					this.querySelector(
22						'.widget_shopping_cart_content'
23					).getBoundingClientRect().bottom + this.offsetHeight,
24				cartList = this.querySelector( '.cart_list' );
25
26			if ( cartBottomPos > windowHeight ) {
27				cartList.style.maxHeight = '15em';
28				cartList.style.overflowY = 'auto';
29			}
30		} );
31	} );
32} )();