[Obj-C] I made the warning disappear by adding the following line to applicationDidFinishLaunching routine in the app delegate: [NSApplication.sharedApplication.keyWindow orderFrontRegardless];

In my non-legal-expert opinion - when you are notarizing an app, you are using the notarizing tool as part of your internal development process. In contrast, of course it would not be permitted to make the notarizing service available to the users of your app.

@astevensflexion Thank you so much. 100% correct. altool method works while notarytool gives HTTP 500 error. Incredible.