Repository: create-react-app
Issue: react-scripts start does not acknowledge changes to env vars in file
Labels: needs triage,issue: bug report

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### Describe the bug

Not sure if this is intended behavior but the live reload functionality behind `react-scripts start` does not acknowledge any changes to environment variables, at least those provided in a file.  I tried with `.env.development.local`.  It's odd that the first time it runs the variables come through but then are never updated on subsequent reloads.  I did not see any note of this in the docs and wasted probably 10 minutes before I just killed it and re-ran the same command to discover that was indeed the problem.

### Did you try recovering your dependencies?

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I was using react-scripts `v5.0.1`

### Which terms did you search for in User Guide?

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Environment variable docs: https://create-react-app.dev/docs/adding-custom-environment-variables/#adding-development-environment-variables-in-env

### Environment

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```
 current version of create-react-app: 5.0.1
  running from /.../.../.npm/cache/_npx/c67e74de0542c87c/node_modules/create-react-app

  System:
    OS: macOS 10.15.7
    CPU: (8) x64 Intel(R) Core(TM) i7-4980HQ CPU @ 2.80GHz
  Binaries:
    Node: 18.14.0 - /usr/local/bin/node
    Yarn: 1.22.19 - ~/.npm-global/bin/yarn
    npm: 9.2.0 - ~/.npm-global/bin/npm
  Browsers:
    Chrome: 118.0.5993.117
    Edge: Not Found
    Safari: 14.0.3
  npmPackages:
    react: ^18.0.0 => 18.2.0 
    react-dom: ^18.0.0 => 18.2.0 
    react-scripts: ^5.0.1 => 5.0.1 
  npmGlobalPackages:
    create-react-app: Not Found
```

### Steps to reproduce

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(Write your steps here:)

1.  Create `.env.development.local` at repo root with a value
2. Run `react-scripts start`
3. Change value in above file, wait for reload or refresh manually
4. Value does not update

### Expected behavior

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Value should update

### Actual behavior

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Value does not update

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