IndexedStack lose focused when switching between index

indexedstack_loss_focus.dart

import 'dart:ui' show window;

import 'package:flutter/material.dart';

void main() {
  runApp(BugReport());
}

class BugReport extends StatefulWidget {
  @override
  _BugReportState createState() => _BugReportState();
}

class _BugReportState extends State<BugReport> {
  int selectedIndex = 0;

  _setIndex(int value) {
    setState(() {
      selectedIndex = value;
    });
  }

  @override
  Widget build(BuildContext context) {
    return Localizations(
      locale: Locale('en', 'US'),
      delegates: [
        DefaultWidgetsLocalizations.delegate,
        DefaultMaterialLocalizations.delegate,
      ],
      child: MediaQuery(
        data: MediaQueryData.fromWindow(window),
        child: Directionality(
          textDirection: TextDirection.ltr,
          child: Navigator(
            onGenerateRoute: (RouteSettings settings) {
              return MaterialPageRoute<void>(
                settings: settings,
                builder: (BuildContext context) {
                  return Material(
                    child: IndexedStack(
                      index: selectedIndex,
                      children: [
                        Center(
                          child: Column(
                            children: [
                              TextField(),
                              OutlineButton(
                                onPressed: () => _setIndex(1),
                                child: Text('Switch to index 1'),
                              ),
                            ],
                          ),
                        ),
                        Center(
                          child: Column(
                            children: [
                              TextField(),
                              OutlineButton(
                                onPressed: () => _setIndex(0),
                                child: Text('Switch to index 0'),
                              ),
                            ],
                          ),
                        ),
                      ],
                    ),
                  );
                },
              );
            },
          ),
        ),
      ),
    );
  }
}

• Issue: flutter/flutter#61659
• Flutter version: 2.10.3
• Tested device: Mac OS Big Sur 11.6 M1
  Chrome 98.0.4758.109 (Official Build) (arm64)
• Replicable: No

61659_indexstack.mp4