I have used firebase and shared_preferences in the main function so I should use the instruction WidgetsFlutterBinding.ensureInitialized(); two times or one enough?
void main() async {
WidgetsFlutterBinding.ensureInitialized();
await Firebase.initializeApp();
WidgetsFlutterBinding.ensureInitialized();
SharedPreferences prefs = await SharedPreferences.getInstance();
.....
runApp( MyApp());
}