TalkerRouteObserver does not work with Navigator widget

[NapasPayu]

Describe the bug
I use TalkerRouteObserver with Navigator widget, but I can't see any logs when navigating.
However, TalkerRiverpodObserver works fine.

dependencies:
talker: ^4.4.1
talker_dio_logger: ^4.4.1
talker_riverpod_logger: ^4.4.1

@override
Widget build(BuildContext context, WidgetRef ref) {
  final talker = Talker();

  return ProviderScope(
    observers: [
      TalkerRiverpodObserver(talker: talker),
    ],
    child: Navigator(
      key: nestedNavigatorKey,
      initialRoute: '/',
      onGenerateRoute: ...,
      observers: [
        TalkerRouteObserver(talker),
      ],
    ),
  );
}