[firebase_messaging] FCM for Flutter Web

[KrzysztofMamak]

Hi, I'm adding an ability to receive push notifications in Flutter Web app. I want to receive push notifications everytime, perform some operation (ex. reload data, update UI in dart code) and not to show system notification. Note that everything works as expected when app is in the foreground. I was based on this example: https://github.com/FirebaseExtended/flutterfire/tree/master/packages/firebase_messaging/firebase_messaging/example.

I have questions:
Am I able to prevent a browser from automatically showing system notification when app is in the background? If yes how can I achieve this?
Can I perform some operation (ex. reload data, update UI in dart code) after receiving push notification when app is in the background?

Thank you in advance.