[web][skwasm] memory access out of bounds in paragraphBuilder_dispose during heavy widget rebuilds

### Steps to reproduce

Steps to reproduce:

Create app with this code
flutter build web --wasm --release
Serve build/web/ without COEP/COOP headers
Open in Chrome 146
Drag items up and down rapidly for 10-20 seconds

### Expected results

Items reorder smoothly, same as canvaskit.

### Actual results

App freezes. Console shows:Uncaught RuntimeError: memory access out of bounds
    at $paragraphBuilder_dispose (skwasm.wasm:0x262225)

Uncaught RuntimeError: memory access out of bounds
    at $textStyle_dispose (skwasm.wasm:0x1fbe17)


### Code sample

<details open><summary>Code sample</summary>

``` dart
import 'package:flutter/material.dart';

void main() => runApp(const MyApp());

class MyApp extends StatelessWidget {
  const MyApp({super.key});
  @override
  Widget build(BuildContext context) => MaterialApp(home: const DragTest());
}

class DragTest extends StatefulWidget {
  const DragTest({super.key});
  @override
  State<DragTest> createState() => _DragTestState();
}

class _DragTestState extends State<DragTest> {
  final items = List.generate(50, (i) => 'Item $i');

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: const Text('Skwasm Drag Crash')),
      body: ReorderableListView.builder(
        itemCount: items.length,
        itemBuilder: (context, index) => ListTile(
          key: ValueKey(items[index]),
          title: Text(items[index]),
          subtitle: Text('Subtitle #$index',
              style: const TextStyle(fontStyle: FontStyle.italic)),
          leading: const Icon(Icons.drag_handle),
        ),
        onReorder: (old, next) {
          setState(() {
            if (next > old) next--;
            items.insert(next, items.removeAt(old));
          });
        },
      ),
    );
  }
}
```

</details>


### Screenshots or Video

<details open>
<summary>Screenshots / Video demonstration</summary>

[Upload media here]

</details>


### Logs

<details open><summary>Logs</summary>


Logs
at skwasm.wasm:0x3c7ef
at skwasm.wasm:0x1fbc43
at main.dart.wasm:0x50734a
at main.dart.wasm:0x505fac
at main.dart.wasm:0x5064b3
at main.dart.wasm:0x4a8ec2Understand this error
skwasm.wasm:0xfd4a Uncaught RuntimeError: memory access out of bounds
at skwasm.wasm:0xfd4a
at skwasm.wasm:0x136622
at skwasm.wasm:0xb982
at skwasm.wasm:0x262006
at main.dart.wasm:0x5049bf
at main.dart.wasm:0x535ae9
at main.dart.wasm:0x53594e
at main.dart.wasm:0xc83e75
at main.dart.wasm:0xc8ac66
at main.dart.wasm:0x53aa6dUnderstand this error
skwasm.wasm:0xedc7 Uncaught RuntimeError: memory access out of bounds
at skwasm.wasm:0xedc7
at skwasm.wasm:0x161ff
at skwasm.wasm:0x14818c
at skwasm.wasm:0x102f0
at skwasm.wasm:0xb7e5f
at skwasm.wasm:0x1af0a
at skwasm.wasm:0xb9776
at skwasm.wasm:0x2782ec
at main.dart.wasm:0x1038ba1
at main.dart.wasm:0x1038bb8Understand this error
skwasm.wasm:0xb8b3 Uncaught RuntimeError: memory access out of bounds
at skwasm.wasm:0xb8b3
at skwasm.wasm:0x21dcbc
at skwasm.wasm:0x1ee228
at skwasm.wasm:0x262225
at main.dart.wasm:0x507399
at main.dart.wasm:0x5073b8
at main.dart.wasm:0x4a910d
at main.dart.wasm:0x4a91a1
at main.dart.wasm:0x48daba
at main.dart.mjs:103:81
$func221 @ skwasm.wasm:0xb8b3
$func9130 @ skwasm.wasm:0x21dcbc
$func8118 @ skwasm.wasm:0x1ee228
$paragraphBuilder_dispose @ skwasm.wasm:0x262225
$func6933 @ main.dart.wasm:0x507399
$func6935 @ main.dart.wasm:0x5073b8
$func2924 @ main.dart.wasm:0x4a910d
$func2929 @ main.dart.wasm:0x4a91a1
$_1663 @ main.dart.wasm:0x48daba
(anonymous) @ main.dart.mjs:103Understand this error
skwasm.wasm:0xb8b3 Uncaught RuntimeError: memory access out of bounds
at skwasm.wasm:0xb8b3
at skwasm.wasm:0x1fbe17
at main.dart.wasm:0x4a90c6
at main.dart.wasm:0x4a912b
at main.dart.wasm:0x4a910d
at main.dart.wasm:0x4a91a1
at main.dart.wasm:0x48daba
at main.dart.mjs:103:81
$func221 @ skwasm.wasm:0xb8b3
$textStyle_dispose @ skwasm.wasm:0x1fbe17
$func2923 @ main.dart.wasm:0x4a90c6
$func2926 @ main.dart.wasm:0x4a912b
$func2924 @ main.dart.wasm:0x4a910d
$func2929 @ main.dart.wasm:0x4a91a1
$_1663 @ main.dart.wasm:0x48daba
(anonymous) @ main.dart.mjs:103Understand this error
main.dart.mjs:73 💓 Sending ping...
main.dart.mjs:73 ⚠️ Pong timeout - missed pongs: 1/3
main.dart.mjs:73 💓 Sending ping...
main.dart.mjs:73 ⚠️ Pong timeout - missed pongs: 2/3
main.dart.mjs:73 💓 Sending ping...
main.dart.mjs:73 ⚠️ Pong timeout - missed pongs: 3/3
main.dart.mjs:73 🔴 Max missed pongs reached - connection considered lost
main.dart.mjs:73 📊 Socket state: reconnecting
main.dart.mjs:73 🔄 Reconnect attempt 1/10 in 1s
main.dart.mjs:73 🧹 Cleaning up socket...
main.dart.mjs:73 📱 App resumed
main.dart.mjs:73 ⚠️ Socket unhealthy - health monitor will handle recovery
main.dart.mjs:73 🔍 Forcing health check...
main.dart.mjs:73 ⚠️ Health check failed - triggering reconnect
main.dart.mjs:73 ⚠️ Reconnection already in progress - skipping
main.dart.wasm:0x477ce0 Uncaught Exception {}
$func1078 @ main.dart.wasm:0x477ce0
$func1074 @ main.dart.wasm:0x477c88
$func8677 @ main.dart.wasm:0x533783
$func9067 @ main.dart.wasm:0x54078e
$func8988 @ main.dart.wasm:0x53ef64
$func8977 @ main.dart.wasm:0x53eb77
$func8972 @ main.dart.wasm:0x53e971
$func9070 @ main.dart.wasm:0x54085c
$func8969 @ main.dart.wasm:0x53e623
$func97856 @ main.dart.wasm:0x1059de0
$func97852 @ main.dart.wasm:0x1059d0d
$func97854 @ main.dart.wasm:0x1059d43
$func2252 @ main.dart.wasm:0x496771
$func2251 @ main.dart.wasm:0x49673e
$func2247 @ main.dart.wasm:0x4966dd
$func2253 @ main.dart.wasm:0x4967b0
$func2255 @ main.dart.wasm:0x4967d5
$func1433 @ main.dart.wasm:0x4889ab
$func1845 @ main.dart.wasm:0x48fa57
$func1847 @ main.dart.wasm:0x48fa74
$_1199 @ main.dart.wasm:0x48d61a
(anonymous) @ main.dart.mjs:212Understand this error
main.dart.mjs:73 📱 App inactive
main.dart.mjs:73 📱 App resumed
main.dart.mjs:73 ⏭️ Socket health check already in progress
main.dart.wasm:0x477ce0 Uncaught Exception {}
$func1078 @ main.dart.wasm:0x477ce0
$func1074 @ main.dart.wasm:0x477c88
$func8677 @ main.dart.wasm:0x533783
$func9067 @ main.dart.wasm:0x54078e
$func8988 @ main.dart.wasm:0x53ef64
$func8977 @ main.dart.wasm:0x53eb77
$func8972 @ main.dart.wasm:0x53e971
$func9070 @ main.dart.wasm:0x54085c
$func8970 @ main.dart.wasm:0x53e62f
$func97856 @ main.dart.wasm:0x1059df1
$func97852 @ main.dart.wasm:0x1059d0d
$func97854 @ main.dart.wasm:0x1059d43
$func2252 @ main.dart.wasm:0x496771
$func2251 @ main.dart.wasm:0x49673e
$func2247 @ main.dart.wasm:0x4966dd
$func2253 @ main.dart.wasm:0x4967b0
$func2255 @ main.dart.wasm:0x4967d5
$func1433 @ main.dart.wasm:0x4889ab
$func1845 @ main.dart.wasm:0x48fa57
$func1847 @ main.dart.wasm:0x48fa74
$_1199 @ main.dart.wasm:0x48d61a
(anonymous) @ main.dart.mjs:212Understand this error
main.dart.mjs:73 📱 App inactive
main.dart.mjs:73 📱 App hidden
main.dart.mjs:73 📱 App inactive
main.dart.mjs:73 📱 App resumed
main.dart.mjs:73 ⏭️ Socket health check already in progress
main.dart.wasm:0x477ce0 Uncaught Exception {}
$func1078 @ main.dart.wasm:0x477ce0
$func1074 @ main.dart.wasm:0x477c88
$func8677 @ main.dart.wasm:0x533783
$func9067 @ main.dart.wasm:0x54078e
$func8988 @ main.dart.wasm:0x53ef64
$func8977 @ main.dart.wasm:0x53eb77
$func8972 @ main.dart.wasm:0x53e971
$func9070 @ main.dart.wasm:0x54085c
$func8970 @ main.dart.wasm:0x53e62f
$func97856 @ main.dart.wasm:0x1059df1
$func97852 @ main.dart.wasm:0x1059d0d
$func97854 @ main.dart.wasm:0x1059d43
$func2252 @ main.dart.wasm:0x496771
$func2251 @ main.dart.wasm:0x49673e
$func2247 @ main.dart.wasm:0x4966dd
$func2253 @ main.dart.wasm:0x4967b0
$func2255 @ main.dart.wasm:0x4967d5
$func1433 @ main.dart.wasm:0x4889ab
$func1845 @ main.dart.wasm:0x48fa57
$func1847 @ main.dart.wasm:0x48fa74
$_1199 @ main.dart.wasm:0x48d61a
(anonymous) @ main.dart.mjs:212Understand this error
main.dart.mjs:73 📱 App inactive
main.dart.mjs:73 📱 App resumed
main.dart.mjs:73 ⏭️ Socket health check already in progress
main.dart.wasm:0x477ce0 Uncaught Exception {}
$func1078 @ main.dart.wasm:0x477ce0
$func1074 @ main.dart.wasm:0x477c88
$func8677 @ main.dart.wasm:0x533783
$func9067 @ main.dart.wasm:0x54078e
$func8988 @ main.dart.wasm:0x53ef64
$func8977 @ main.dart.wasm:0x53eb77
$func8972 @ main.dart.wasm:0x53e971
$func9070 @ main.dart.wasm:0x54085c
$func8969 @ main.dart.wasm:0x53e623
$func97856 @ main.dart.wasm:0x1059de0
$func97852 @ main.dart.wasm:0x1059d0d
$func97854 @ main.dart.wasm:0x1059d43
$func2252 @ main.dart.wasm:0x496771
$func2251 @ main.dart.wasm:0x49673e
$func2247 @ main.dart.wasm:0x4966dd
$func2253 @ main.dart.wasm:0x4967b0
$func2255 @ main.dart.wasm:0x4967d5
$func1433 @ main.dart.wasm:0x4889ab
$func1845 @ main.dart.wasm:0x48fa57
$func1847 @ main.dart.wasm:0x48fa74
$_1199 @ main.dart.wasm:0x48d61a
(anonymous) @ main.dart.mjs:212Understand this error
main.dart.mjs:73 📱 App inactive
main.dart.mjs:73 📱 App hidden
main.dart.mjs:73 📱 App inactive
main.dart.mjs:73 📱 App resumed
main.dart.mjs:73 ⏭️ Socket health check already in progress
</details>


### Flutter Doctor output

<details open><summary>Doctor output</summary>


Doctor output
[✓] Flutter (Channel stable, 3.41.2, on macOS 26.3.1 25D771280a darwin-arm64, locale en) [1,740ms]
• Flutter version 3.41.2 on channel stable at /Users/Tarun/fvm/versions/3.41.2
• Upstream repository https://github.com/flutter/flutter.git
• Framework revision https://github.com/flutter/flutter/commit/90673a4eef275d1a6692c26ac80d6d746d41a73a (7 weeks ago), 2026-02-18 13:54:59 -0800
• Engine revision https://github.com/flutter/flutter/commit/6c0baaebf70e0148f485f27d5616b3d3382da7bf
• Dart version 3.11.0
• DevTools version 2.54.1
• Feature flags: enable-web, enable-linux-desktop, enable-macos-desktop, enable-windows-desktop, enable-android, enable-ios, cli-animations, enable-native-assets,
omit-legacy-version-file, enable-lldb-debugging, enable-uiscene-migration

[!] Android toolchain - develop for Android devices (Android SDK version 30.0.3) [8.1s]
• Android SDK at /Users/Tarun/Library/Android/sdk
• Emulator version 31.3.13.0 (build_id 9189900) (CL:N/A)
✗ Flutter requires Android SDK 36 and the Android BuildTools 28.0.3
To update the Android SDK visit https://flutter.dev/to/macos-android-setup for detailed instructions.
! Some Android licenses not accepted. To resolve this, run: flutter doctor --android-licenses

[✓] Xcode - develop for iOS and macOS (Xcode 26.2) [3.3s]
• Xcode at /Applications/Xcode.app/Contents/Developer
• Build 17C52
• CocoaPods version 1.16.2

[✓] Chrome - develop for the web [6ms]
• Chrome at /Applications/Google Chrome.app/Contents/MacOS/Google Chrome

[✓] Connected device (2 available) [7.0s]
• macOS (desktop) • macos • darwin-arm64 • macOS 26.3.1 25D771280a darwin-arm64
• Chrome (web) • chrome • web-javascript • Google Chrome 147.0.7727.56
! Error: Browsing on the local area network for iPhone. 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 [297ms]
• All expected network resources are available.

! Doctor found issues in 1 category.

</details>


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[web][skwasm] memory access out of bounds in paragraphBuilder_dispose during heavy widget rebuilds #184858

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[web][skwasm] memory access out of bounds in paragraphBuilder_dispose during heavy widget rebuilds #184858

Description

Steps to reproduce

Expected results

Actual results

Code sample

Screenshots or Video

Logs

Flutter Doctor output

Metadata

Metadata

Assignees

Labels

Type

Fields

Projects

Milestone

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Development

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