Absent POST data in checkout causing compatibility errors

[Mark-Ernst]

We develop the Woocommerce MyParcel plugin for Woocommerce that helps customers print shipping labels. In order to get the chosen shipping method for each customer, we read the 'shipping_methods' field which Woocommerce provides in the post data after checkout. Apparently the Mollie plugin removes this field, causing a broken checkout when customers use both our plugin and the Mollie plugin. It would be ideal for us and probably other plugins that are dependent on the shipping_methods field that this data is preserved.