Shopping Cart Version
At present, the following JavaScript is required to enable the version 2 of the cart.
This script can be placed in your Wordpress theme's header.php file inside <script></script>
tags.
You can edit this file by going to Appearance > Theme Editor > header.php.
This functionality may be supported through plugin options in a future version.
Enable WithWine Cart Version 2
window.WITHWINE_CART_VERSION === 2;