apiv1

...
import 'package:window_manager/window_manager.dart';

void main() async {
  WidgetsFlutterBinding.ensureInitialized();
  await windowManager.ensureInitialized();

  windowManager.waitUntilReadyToShow(null, () async {
    await windowManager.setFullScreen(true);
  });

  runApp(const MyApp());
}