Following the "Install Flutter manually" resulted to error

### Page URL

https://docs.flutter.dev/install/manual/

### Page source

https://github.com/flutter/website/tree/main/src/content/install/manual.md

### Describe the problem

After downloading the flutter sdk, unzipping and moving it to preferred directory, I tried checking it by running `flutter --version` but it resulted to error:

```bash
$ flutter --version
Error: The Flutter directory is not a clone of the GitHub project.
The flutter tool requires Git in order to operate properly;
to install Flutter, see the instructions at:
https://flutter.dev/get-started
```

same with dart

```bash
dart --version
Error: The Flutter directory is not a clone of the GitHub project.
The flutter tool requires Git in order to operate properly;
to install Flutter, see the instructions at:
https://flutter.dev/get-started
```

### Expected fix

Following the instruction should resulted to successful flutter installation.

### Additional context

What I did for now is, remove the downloaded sdk and clone the stable version instead.

```bash
git clone https://github.com/flutter/flutter.git -b stable
```

Running `flutter --version` gives expected result
```bash
flutter --version
Flutter 3.35.6 • channel stable • https://github.com/flutter/flutter.git
Framework • revision 9f455d2486 (9 days ago) • 2025-10-08 14:55:31 -0500
Engine • hash a5f2c36e367c13f868cfe98db5806f562c52c35e (revision d2913632a4) (10 days ago) • 2025-10-07 17:26:21.000Z
Tools • Dart 3.9.2 • DevTools 2.48.0
```

### I would like to fix this problem.

- [ ] I will try and fix this problem on docs.flutter.dev.