I have a simple app that uses the Firebase Cloud Messaging service (the firebase_messaging package) to send push notifications to mobile devices. After following and applying the official setup documentation on both devices, the library documentation suggests that the statement of FirebaseMessaging.onBackgroundMessage(...) registers a function to be executed in the background in the future as a means of capturing the incoming RemoteMessage. However, this function is only supposed to run while the app is in the background. Yet, it is running on Android but not on iOS. What could be causing this problem?
