iOS 15.5 Beta Adds Support for External Links Amid Upcoming Changes for Reader Apps

Apple has recently implemented several changes to the App Store that allow for outside payment options and linking to external websites for purchase purposes. As part of these changes, Apple in iOS 15.5 is adding support for and warnings about external purchases.
Code for external purchase support was discovered by 9to5Mac in the iOS 15.5 beta, which came out yesterday. The site says that iOS 15.5 "has full support" for the "External Link Account Entitlement" that Apple recently made available t