Repository: create-react-app
Issue: Can't get .env.development && .env.production variable
Labels: stale,needs triage,issue: bug report

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### Describe the bug

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### Environment

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### Steps to reproduce

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(Write your steps here:)
1. add .env.developent in root path
2. add content into the .env.developent
```

REACT_APP_CHAIN_ID = "42"

# 10+ nodes balanced, US/EU
REACT_APP_NODE_1 = "https://kovan.infura.io"

# 10+ nodes balanced, US/EU
REACT_APP_NODE_2 = "https://kovan.infura.io"

# 10+ nodes balanced in each region, global
REACT_APP_NODE_3 = "https://kovan.infura.io"
```

3. in the App.js to process.env.REACT_APP_NODE_1 can't get the data, is undefined

### Expected behavior

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### Actual behavior

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