The Donation Confirmation modal window appears when a donation has been successfully generated. The window will show the donation amount that their purchase generated, your store name and what cause or nonprofit the donation will support. The customer has the option to share on Facebook and/or Twitter also allowing the customer to write a message to garner support from their community. They will also learn they can track their donations on ShoppingGives by creating an account.
You can disable the Donation Modal Confirmation on Shopify Admin. However, in order to disable the Modal Confirmation, you must have Email Confirmation enabled.