Repository: flutter
Issue: Flutter desktop web support for Microsoft Edge Read Aloud
Labels: c: new feature,a: accessibility,platform-windows,platform-web,P3,c: parity,team-web,triaged-web

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Microsoft [Read Aloud](https://www.microsoft.com/en-us/edge/features/read-aloud) provides accessibility on reading through web pages. However, Read Aloud is unable to read text displayed on Flutter web apps.

## Steps to Reproduce

<!-- Please include full steps to reproduce so that we can reproduce the problem. -->

1.  Using Microsoft Edge, go to https://gallery.flutter.dev/#/reply
2. Click 'Read Aloud' available on the address bar. The 'Read Aloud' function can also be accessible from the menu. 
<img width="292" alt="Screenshot 2023-02-22 at 1 55 45 AM" src="https://user-images.githubusercontent.com/4143153/220422911-8a2c606a-7797-4a07-a349-71d26ffe89c9.png">

3. A toolbar for Read Aloud should appear and start reading the text available on the page.

**Expected results:** <!-- what did you want to see? -->

Read Aloud should be able to read text displayed in Flutter web on desktop.

**Actual results:** <!-- what did you see? -->

Read Aloud is unable to read the text displayed in Flutter web on desktop.

<details>
<summary>Code sample</summary>

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```dart
```

</details>

<details>
  <summary>Logs</summary>

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```
```

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```
```

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```
```

</details>


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