Repository: create-react-app
Issue: Bump react-scripts from 3.4.3 to 4.0.1 Fails
Labels: needs triage,issue: bug report

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### Describe the bug
![image](https://user-images.githubusercontent.com/65172537/103546903-addaca00-4e71-11eb-95bd-6508b949d201.png)
![image](https://user-images.githubusercontent.com/65172537/103547467-6bfe5380-4e72-11eb-9d42-bab4b3157ae6.png)

(Write your answer here.)
Version 4.0.1 is broken:
- Open up dependabot pull requests
- Go to Bump react-scripts from 3.4.3 to 4.0.1
- Note: I do not see breaking changes listed
- Compatibility is @ 57%
- There are build errors here on your repo
### Did you try recovering your dependencies?
n/a
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    yarn

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### Which terms did you search for in User Guide?
The change log in the dependabot PR
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### Environment

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run `yarn build`
(paste the output of the command here.)
confidential...
### Steps to reproduce
Upgrade to 4.0.1, run your existing react scripts (i.e. yarn start, yarn build, etc.)
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(Write your steps here:)

1. Install new dependancy 4.0.1
2. Run existing scripts
3. Errors, but I can't seem to find guidance on breaking changes
![image](https://user-images.githubusercontent.com/65172537/103547299-39545b00-4e72-11eb-9903-ca86b1ed5fa7.png)

### Expected behavior

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- Breaking changes are listed
- Per breaking changes list, I can update my app
- Then re-install 4.0.1 and the app works
### Actual behavior

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