Accessing cart->cart_contents directly :(

In includes/helpers.php you are accessing the cart contents directly instead of using the getter function of the class.

$cart_contents = $woocommerce->cart->cart_contents;

Besides being bad practice, this in effect bypasses the filter provided by WooCommerce ‘woocommerce_get_cart_contents’

A better and more developer-friendly method would be to use the getter

$cart_contents = $woocommerce->cart->get_cart();