macOS version of apps can be included in a universal purchase

Apple’s Developer website notes that the macOS version of your app can now be included in a universal purchase.

This allows customers to buy an app and in‑app purchases across iOS, iPadOS, macOS, watchOS, and tvOS by purchasing only once. Developers can get started by using a single bundle ID for their apps in Xcode and setting up their app record for universal purchase in App Store Connect.