The source node in most cases contains the sample message as written by the developer. If it looks like a dot-delimitted string such as "form.label.firstname", then the developer has not provided a default message.

Continue shopping Continue shopping key: ibexa_storefront.checkout.layout.continue.shopping key: ibexa_storefront.checkout.select_address.submit Go to payment method Go to payment method key: ibexa_storefront.checkout.select_payment.submit Go to Payment and summary Go to Payment and summary key: ibexa_storefront.checkout.select_shipping.submit Order Order key: ibexa_storefront.checkout.summary.quick_summary.label Go to summary Go to summary key: ibexa_storefront.checkout.summary.submit Subtotal Subtotal key: ibexa_storefront.checkout.summary.subtotal