With iOS one had to test the subscriptions on a hardware device. Can we test Mac App subscriptions from Xcode?
I get stuck in a loop where I get asked to log into my Apple ID.
maccatalyst subscriptions testing
While I could test my iOS app in TestFlight using my real Apple ID, I found that I had to use a sandbox tester account to test it when using Mac Catalyst. See Create a sandbox tester account in the App Store Connect Help.