Repository: create-react-app
Issue: PUBLIC_URL is not the same as homepage, but only the pathname
Labels: issue: bug report

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### Describe the bug

I have uploaded  all the static resources to CDN, include .js and .css files.  So I have to set the 'homepage' as the host address of CDN server, which make the urls of scripts in 'index.html' to be right.

However, the urls injected to 'index.html' is the pathname of 'homepage' that I set in package.json, after upload react-scripts to 3.4.1.

And there is no such problem when I using version 3.3.0. I found that the actual homepage has been change after this PR [feat(react-scripts): allow PUBLIC_URL in develoment mode](https://github.com/facebook/create-react-app/pull/7259)
 
So I want to know, is it a bug that will be fixed? Or is there any method that can make the PUBLIC_URL to be a complete url.

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no, but downgrade to 3.3.0

### Which terms did you search for in User Guide?

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The docs still use the complete url as example [Step 1: Add homepage to package.json](https://create-react-app.dev/docs/deployment#step-1-add-homepage-to-packagejson)

### Environment

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irrelevant, i guess

### Steps to reproduce

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(Write your steps here:)

1. set homepage in package.json like 'https://example.com/a/b/c'
2. yarn build
3. the url of script in index.html will be '/a/b/c/xxx.js', which will not find the correct resource

### Expected behavior

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The PUBLIC_URL should  be the same as homepage in package.json

### Actual behavior

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The PUBLIC_URL is the pathname of homepage

### Reproducible demo

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no demo

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