Repository: create-react-app
Issue: Getting error when enabling FAST_REFRESH flag
Labels: needs triage,issue: bug report

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### Describe the bug

Getting following error when enabling FAST_REFRESH flag

![image](https://user-images.githubusercontent.com/8564518/101272972-2f7a0200-37b7-11eb-933e-fb4ab912294a.png)


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### Environment

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