In some cases, you may see a "Liquid error:internal" message instead of the product images in your document.
This error message can appear in documents if the person using the Shopify Order Printer app does not have permissions for "Products" on their staff account.
For some reason, the Shopify Order Printer app requires that a user has permission for Products for the product images to display correctly and avoid the error message.
Note: This applies if the error message appears in ALL products listed in the document.