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[Web] Hot Reload jumping on binding.dart file even if "uncaught exceptions" are turned off #176693

@AbhishekDoshi26

Description

@AbhishekDoshi26

Steps to reproduce

  1. Create a new project (default project)
  2. Run on web
  3. Do hot reload

Expected results

Hot reload should work fine without jumping on binding.dart file

Actual results

As soon as hot reload happens, system jumps on binding.dart file

Code sample

Code sample
import 'package:flutter/material.dart';

void main() {
  runApp(const MyApp());
}

class MyApp extends StatelessWidget {
  const MyApp({super.key});

  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        // This is the theme of your application.
        //
        // TRY THIS: Try running your application with "flutter run". You'll see
        // the application has a purple toolbar. Then, without quitting the app,
        // try changing the seedColor in the colorScheme below to Colors.green
        // and then invoke "hot reload" (save your changes or press the "hot
        // reload" button in a Flutter-supported IDE, or press "r" if you used
        // the command line to start the app).
        //
        // Notice that the counter didn't reset back to zero; the application
        // state is not lost during the reload. To reset the state, use hot
        // restart instead.
        //
        // This works for code too, not just values: Most code changes can be
        // tested with just a hot reload.
        colorScheme: ColorScheme.fromSeed(seedColor: Colors.deepPurple),
      ),
      home: const MyHomePage(title: 'Flutter Demo Home Page'),
    );
  }
}

class MyHomePage extends StatefulWidget {
  const MyHomePage({super.key, required this.title});

  // This widget is the home page of your application. It is stateful, meaning
  // that it has a State object (defined below) that contains fields that affect
  // how it looks.

  // This class is the configuration for the state. It holds the values (in this
  // case the title) provided by the parent (in this case the App widget) and
  // used by the build method of the State. Fields in a Widget subclass are
  // always marked "final".

  final String title;

  @override
  State<MyHomePage> createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  int _counter = 0;

  void _incrementCounter() {
    setState(() {
      // This call to setState tells the Flutter framework that something has
      // changed in this State, which causes it to rerun the build method below
      // so that the display can reflect the updated values. If we changed
      // _counter without calling setState(), then the build method would not be
      // called again, and so nothing would appear to happen.
      _counter++;
    });
  }

  @override
  Widget build(BuildContext context) {
    // This method is rerun every time setState is called, for instance as done
    // by the _incrementCounter method above.
    //
    // The Flutter framework has been optimized to make rerunning build methods
    // fast, so that you can just rebuild anything that needs updating rather
    // than having to individually change instances of widgets.
    return Scaffold(
      appBar: AppBar(
        // TRY THIS: Try changing the color here to a specific color (to
        // Colors.amber, perhaps?) and trigger a hot reload to see the AppBar
        // change color while the other colors stay the same.
        backgroundColor: Theme.of(context).colorScheme.inversePrimary,
        // Here we take the value from the MyHomePage object that was created by
        // the App.build method, and use it to set our appbar title.
        title: Text(widget.title),
      ),
      body: Center(
        // Center is a layout widget. It takes a single child and positions it
        // in the middle of the parent.
        child: Column(
          // Column is also a layout widget. It takes a list of children and
          // arranges them vertically. By default, it sizes itself to fit its
          // children horizontally, and tries to be as tall as its parent.
          //
          // Column has various properties to control how it sizes itself and
          // how it positions its children. Here we use mainAxisAlignment to
          // center the children vertically; the main axis here is the vertical
          // axis because Columns are vertical (the cross axis would be
          // horizontal).
          //
          // TRY THIS: Invoke "debug painting" (choose the "Toggle Debug Paint"
          // action in the IDE, or press "p" in the console), to see the
          // wireframe for each widget.
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            const Text('You have pushed the button this many times:'),
            Text(
              '$_counter',
              style: Theme.of(context).textTheme.headlineMedium,
            ),
          ],
        ),
      ),
      floatingActionButton: FloatingActionButton(
        onPressed: _incrementCounter,
        tooltip: 'Increment',
        child: const Icon(Icons.add),
      ), // This trailing comma makes auto-formatting nicer for build methods.
    );
  }
}

GitHub: https://github.com/AbhishekDoshi26/flutter_web_hot_reload

Screenshots or Video

Screenshots / Video demonstration
Screen.Recording.2025-10-08.at.1.00.40.PM.mov

Logs

No response

Flutter Doctor output

Doctor output
[✓] Flutter (Channel stable, 3.35.5, on macOS 26.0.1 25A362 darwin-arm64, locale en-GB) [478ms]
    • Flutter version 3.35.5 on channel stable at /Users/abhishekdoshi/Desktop/flutter
    • Upstream repository https://github.com/flutter/flutter.git
    • Framework revision ac4e799d23 (12 days ago), 2025-09-26 12:05:09 -0700
    • Engine revision d3d45dcf25
    • Dart version 3.9.2
    • DevTools version 2.48.0
    • Feature flags: enable-web, enable-linux-desktop, enable-macos-desktop, enable-windows-desktop, enable-android, enable-ios, cli-animations, enable-lldb-debugging

[!] Android toolchain - develop for Android devices (Android SDK version 35.0.0) [2.3s]
    • Android SDK at /Users/abhishekdoshi/Library/Android/sdk
    • Emulator version 30.9.4.0 (build_id 7759208) (CL:N/A)
    • Platform android-35, build-tools 35.0.0
    • Java binary at: /Users/abhishekdoshi/Library/Java/JavaVirtualMachines/corretto-17.0.12/Contents/Home/bin/java
      This JDK is specified in your Flutter configuration.
      To change the current JDK, run: `flutter config --jdk-dir="path/to/jdk"`.
    • Java version OpenJDK Runtime Environment Corretto-17.0.12.7.1 (build 17.0.12+7-LTS)
    ! Some Android licenses not accepted. To resolve this, run: flutter doctor --android-licenses

[✓] Xcode - develop for iOS and macOS (Xcode 16.4) [1,676ms]
    • Xcode at /Applications/Xcode.app/Contents/Developer
    • Build 16F6
    • CocoaPods version 1.16.2

[✓] Chrome - develop for the web [9ms]
    • Chrome at /Applications/Google Chrome.app/Contents/MacOS/Google Chrome

[✓] Android Studio (version 2024.1) [8ms]
    • Android Studio at /Applications/Android Studio.app/Contents
    • Flutter plugin can be installed from:
      🔨 https://plugins.jetbrains.com/plugin/9212-flutter
    • Dart plugin can be installed from:
      🔨 https://plugins.jetbrains.com/plugin/6351-dart
    • Java version OpenJDK Runtime Environment (build 17.0.11+0-17.0.11b1207.24-11852314)

[✓] VS Code (version 1.104.3) [6ms]
    • VS Code at /Applications/Visual Studio Code.app/Contents
    • Flutter extension version 3.120.0

[✓] Connected device (3 available) [6.1s]
    • Abhishek’s iPhone (wireless) (mobile) • 00008110-001478AE113A801E • ios            • iOS 26.0.1 23A355
    • macOS (desktop)                       • macos                     • darwin-arm64   • macOS 26.0.1 25A362 darwin-arm64
    • Chrome (web)                          • chrome                    • web-javascript • Google Chrome 141.0.7390.65
    ! Error: Browsing on the local area network for Abhishek’s iPad. Ensure the device is unlocked and attached with a cable or associated with the same local area network as this Mac.
      The device must be opted into Developer Mode to connect wirelessly. (code -27)

[✓] Network resources [437ms]
    • All expected network resources are available.

! Doctor found issues in 1 category.

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    c: regressionIt was better in the past than it is nowfound in release: 3.35Found to occur in 3.35found in release: 3.37Found to occur in 3.37frameworkflutter/packages/flutter repository. See also f: labels.has reproducible stepsThe issue has been confirmed reproducible and is ready to work onr: fixedIssue is closed as already fixed in a newer versiont: hot reloadReloading code during "flutter run"toolAffects the "flutter" command-line tool. See also t: labels.workaround availableThere is a workaround available to overcome the issue

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