Repository: create-react-app
Issue: Numeric separators break development mode
Labels: stale,needs triage,issue: bug report

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### Describe the bug


`Numeric separators` in `node_modules` after installing [color@4.0.1](https://github.com/Qix-/color) causes the app to break when running in development mode with `npm start` or `yarn start`.

### Did you try recovering your dependencies?

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Yes.

```
$  yarn --version
1.22.11
```

```
$  npm --version
7.21.1
```

### Which terms did you search for in User Guide?

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- Numeric separators
- Module parse failed: Identifier directly after number
- Babel loaders

### Environment

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```
Environment Info:

  current version of create-react-app: 4.0.3
  running from /home/rfmaj/.npm/_npx/c67e74de0542c87c/node_modules/create-react-app

  System:
    OS: Linux 5.4 Ubuntu 20.04.3 LTS (Focal Fossa)
    CPU: (16) x64 AMD Ryzen 7 2700X Eight-Core Processor
  Binaries:
    Node: 14.17.5 - ~/.volta/tools/image/node/14.17.5/bin/node
    Yarn: 1.22.11 - ~/.volta/tools/image/yarn/1.22.11/bin/yarn
    npm: 7.21.1 - ~/.volta/tools/image/npm/7.21.1/bin/npm
  Browsers:
    Chrome: Not Found
    Firefox: Not Found
  npmPackages:
    react: ^17.0.2 => 17.0.2
    react-dom: ^17.0.2 => 17.0.2
    react-scripts: 4.0.3 => 4.0.3
  npmGlobalPackages:
    create-react-app: Not Found
```

### Steps to reproduce

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1. Create a new app: `npx create-react-app numeric-separators`
2. Cd into the new created app: `cd numeric-separators`
3. Install `color`: `yarn add color@4.0.1` (latest version atm)
4. Import color in `src/App.js`: `import Color from 'color'` ([example](https://github.com/MauricioRobayo/numeric-separators-issue/blob/23baf46ad53d850e3abaf8bb92c95fd241a24e2f/src/App.js#L3))
5. Start development mode with `yarn start`
**Note**: Building the app with `yarn build` works fine.

### Expected behavior

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App starts normally in development mode.

### Actual behavior

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App fails to compile with following error:

```
Failed to compile.

./node_modules/color/index.js 246:28
Module parse failed: Identifier directly after number (246:28)
File was processed with these loaders:
 * ./node_modules/react-scripts/node_modules/babel-loader/lib/index.js
You may need an additional loader to handle the result of these loaders.
|     for (const [i, element] of rgb.entries()) {
|       const chan = element / 255;
>       lum[i] = chan <= 0.039_28 ? chan / 12.92 : ((chan + 0.055) / 1.055) ** 2.4;
|     }
|
```

![image](https://user-images.githubusercontent.com/2121481/132343457-2fd7c776-ac6b-43f6-b277-bd7573720775.png)

### Reproducible demo

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Example project: https://github.com/MauricioRobayo/numeric-separators-issue

Steps to reproduce it:

1. Clone the repo: `git clone https://github.com/MauricioRobayo/numeric-separators-issue`
2. cd into the repo: `cd numeric-separators-issue`
3. Install dependencies: `yarn`
4. Start the app in development mode: `yarn start`

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