Repository: create-react-app
Issue: react-scripts@5 BROWSER in .env file is not working
Labels: needs triage,issue: bug report

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### Describe the bug

With react-scripts@5 BROWSER is not working when placed in an .env file (I'm using .env.local in this case)

i.e. BROWSER=msedge used to work with react-scripts@4, with v5 this is ignored and the default browser opens

### Did you try recovering your dependencies?

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Node version: 16.13.2
NPM version: 8.3.1

### Which terms did you search for in User Guide?

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Following guide here: https://create-react-app.dev/docs/advanced-configuration/

### Environment

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Environment Info:

  current version of create-react-app: 5.0.0
  running from C:\Users\[username]\scoop\persist\nodejs-lts\cache\_npx\c67e74de0542c87c\node_modules\create-react-app

  System:
    OS: Windows 10 10.0.19044
    CPU: (12) x64 Intel(R) Xeon(R) E-2176M  CPU @ 2.70GHz
  Binaries:
    Node: 16.13.2 - ~\scoop\apps\nodejs-lts\current\node.EXE
    Yarn: Not Found
    npm: 8.3.1 - ~\scoop\apps\nodejs-lts\current\bin\npm.CMD
  Browsers:
    Chrome: 97.0.4692.71
    Edge: Spartan (44.19041.1266.0), Chromium (97.0.1072.62)
    Internet Explorer: Not Found
  npmPackages:
    react: ^17.0.2 => 17.0.2
    react-dom: ^17.0.2 => 17.0.2
    react-scripts: 5.0.0 => 5.0.0
  npmGlobalPackages:
    create-react-app: Not Found

### Steps to reproduce

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1. set BROWSER in .env.local file
2. `npm start`

### Expected behavior

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Specified browser opens

### Actual behavior

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System default browser opens, not as specified above