Repository: flutter
Issue: Thai tone symbols not appearing on mobile web
Labels: engine,platform-web,e: web_html,has reproducible steps,P2,c: parity,found in release: 3.3,found in release: 3.6,team-web,triaged-web

I made an app for learning Thai and it has been released as an iOS/Android app and web (https://www.longtailthai.com/)

The app shows the tones of syllables with 4 different tone symbols, you can see those on https://easythai.net

It seems after recent Flutter upgrade (3.3.8) the tone symbols are not visible anymore on mobile web, both iOS and Android, I have tested Chrome, Firefox and Safari

This works as expected on Android, iOS, Windows desktop, and Windows web (Chrome, Firefox)

## To reproduce

1. Open  https://easythai.net on mobile (iPhone or Android)

#### Expected
Tone symbols following "low", "falling", "high" and "rising" are visible

![image](https://user-images.githubusercontent.com/95013472/201057604-25779114-94c5-4759-ab9e-0c7a994643a0.png)

#### Actual
The tone symbols following "low", "falling", "high" and "rising" are not visible

![image](https://user-images.githubusercontent.com/95013472/201057979-045fd551-d5ae-4b9e-a460-47545f6127ff.png)

## main.dart
```
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(
        primarySwatch: Colors.blue,
      ),
      home: const MyHomePage(title: 'Flutter Demo Home Page'),
    );
  }
}

class MyHomePage extends StatefulWidget {

  const MyHomePage({super.key, required this.title});

  final String title;

  @override
  State<MyHomePage> createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {

  final FocusNode focusNode = FocusNode();
  final String risingToneMark = '๋';
  final String highToneMark = '๊';
  final String fallingToneMark = '้';
  final String lowToneMark = '่';

  @override
  Widget build(BuildContext context) {

    FocusScope.of(context).requestFocus(focusNode);

    return Scaffold(
      appBar: AppBar(
        title: Text(widget.title),
      ),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            _getLowWidget('low'),
            _getFallingWidget('falling'),
            _getHighWidget('high'),
            _getRisingWidget('rising')
          ],
        ),
      ),
    );
  }

  Widget _getLowWidget(String text) {

    return Container(
        padding: const EdgeInsets.only(left: 5, right: 3, top: 2, bottom: 2),
        margin: EdgeInsets.all(10),
        decoration: BoxDecoration(borderRadius: BorderRadius.circular(5), color: Colors.red),
        child: Stack(children: [
          Container(margin: const EdgeInsets.only(right: 10), child: Text(text, style: TextStyle(fontSize: 14),)),
          Positioned(right: 1,
              top: 2,
              child: Text(' $lowToneMark', style: TextStyle(fontSize: 25, color: Colors.black, fontFamily: 'Sarabun'))),
        ],));
  }

  Widget _getHighWidget(String text) {

    return Container(
        padding: const EdgeInsets.only(left: 5, right: 3, top: 2, bottom: 2),
        margin: EdgeInsets.all(10),
        decoration: BoxDecoration(borderRadius: BorderRadius.circular(5), color: Colors.red),
        child: Stack(children: [Container(
          margin: const EdgeInsets.only(right: 16),
          child: Text(text, style: TextStyle(fontSize: 14)),
        ),
          Positioned(right: 2,
              top: 3,
              child: Text(' $highToneMark', style: TextStyle(fontSize: 22, color: Colors.black, fontFamily: 'Sarabun'))),
        ],));
  }

  Widget _getFallingWidget(String text) {

    return Container(
        padding: const EdgeInsets.only(left: 5, right: 3, top: 2, bottom: 2),
        margin: EdgeInsets.all(10),
        decoration: BoxDecoration(borderRadius: BorderRadius.circular(5), color: Colors.red),
        child: Stack(children: [Container(margin: const EdgeInsets.only(right: 13), child: Text(text, style: TextStyle(fontSize: 14))),
          Positioned(right: 2,
              top: 3,
              child: Text(' $fallingToneMark', style: TextStyle(fontSize: 22, color: Colors.black, fontFamily: 'Sarabun'),)),
        ],));
  }

  Widget _getRisingWidget(String text) {
    return Container(
        padding: const EdgeInsets.only(left: 5, right: 3, top: 2, bottom: 2),
        margin: EdgeInsets.all(10),
        decoration: BoxDecoration(borderRadius: BorderRadius.circular(5), color: Colors.red),
        child: Stack(children: [Container(margin: const EdgeInsets.only(right: 12), child: Text(text, style: TextStyle(fontSize: 14))),
          Positioned(right: 2,
              top: 2,
              child: Text(' $risingToneMark', style: TextStyle(fontSize: 25, color: Colors.black, fontFamily: 'Sarabun'),)),
        ],));
  }
}
```

## pubspec.yaml

```
name: test1
description: A new Flutter project.

publish_to: 'none' # Remove this line if you wish to publish to pub.dev

version: 1.0.0+1

environment:
  sdk: '>=2.18.0 <3.0.0'

dependencies:
  flutter:
    sdk: flutter

  cupertino_icons: ^1.0.2

dev_dependencies:
  flutter_test:
    sdk: flutter

  flutter_lints: ^2.0.0

flutter:

  uses-material-design: true

  fonts:
    - family: Sarabun
      fonts:
        - asset: fonts/Sarabun/Sarabun-Regular.ttf
        - asset: fonts/Sarabun/Sarabun-Medium.ttf
```

## Flutter doctor

Doctor summary (to see all details, run flutter doctor -v):
[√] Flutter (Channel stable, 3.3.8, on Microsoft Windows [Version 10.0.22000.1219], locale en-GB)
[√] Android toolchain - develop for Android devices (Android SDK version 33.0.0)
[√] Chrome - develop for the web
[√] Visual Studio - develop for Windows (Visual Studio Community 2022 17.4.0)
[√] Android Studio (version 2021.3)
[√] VS Code (version 1.73.0)
[√] Connected device (3 available)
[√] HTTP Host Availability

• No issues found!

## Project file

https://www.easythai.net/FlutterTest.zip