I’m trying to override a widget variable using mixin , but I get the following error Uncaught TypeError: target.extend is not a function the original file is define([ "underscore", "jquery", "knockout", 'amShopbyTopFilters', "productListToolbarForm", "amShopbyFilterAbstract", "Magento_PageCache/js/page-cache" ], function (_, $, ko, amShopbyTopFilters) { 'use strict'; $.widget('mage.amShopbyAjax', { prevCall: false, $shopbyOverlay: null, […]