Cannot use minified library written ES6 in RCA

Created by: pomek

Is this a bug report?

Yes.

Did you try recovering your dependencies?

Yes.

Which terms did you search for in User Guide?

I didn't find anything that could help me. I was searching for something that allows me to disable transpiling a library that was written ES6 and also minified.

Environment

node -v
v10.11.0

npm -v
6.4.1

Steps to Reproduce

Clone a demo (on the bottom of this comment) or follow steps listed below:

Create an example app: npx create-react-app my-app
Install CKEditor 5 dependencies: npm install @ckeditor/ckeditor5-react @ckeditor/ckeditor5-build-classic
Replace src/App.js with:

import React, { Component } from 'react';
import CKEditor from '@ckeditor/ckeditor5-react';
import ClassicEditor from '@ckeditor/ckeditor5-build-classic';
import './App.css';

class App extends Component {
	render() {
		return (
			<div className="App">
				<CKEditor
					editor={ClassicEditor}
					data="<p>Hello from CKEditor 5!</p>"
					onInit={editor => {
						// You can store the "editor" and use when it's needed.
						console.log( 'Editor is ready to use!', editor );
					}}
					onChange={( event, editor ) => {
						const data = editor.getData();
						console.log( { event, editor, data } );
					}}
				/>
			</div>
		);
	}
}

export default App;

npm start

Expected Behavior

The application works, the dev-tools console does not contain any error.

Actual Behavior

A blank page and the following error in the console.

Additional informations

I wanted to check whether it will work if ckeditor5-build-classic won't be minified so I did steps specified below:

Go to @ckeditor namespace in dependencies: cd node_modules/@ckeditor
Remove ckeditor5-build-classic installed from npm: rm -r ckeditor5-build-classic
Clone package from GitHub and check out to the proper version: git clone -b v11.1.0 git@github.com:ckeditor/ckeditor5-build-classic.git
Go to the package and install dependencies: cd ckeditor5-build-classic && npm i
Build the package in development mode: ./node_modules/.bin/webpack --mode development
Go back to your application and call npm start again.

It works!

The question is - why doesn't minified build work?

Reproducible Demo

https://github.com/pomek/react-app