Console error "Setting up fake worker failed" while using in React

Attach (recommended) or Link to PDF file here: https://www.w3.org/WAI/ER/tests/xhtml/testfiles/resources/pdf/dummy.pdf

Configuration:

• Web browser and its version: Chrome 83.0.4103.116
• Operating system and its version: MacOS 10.14.6
• PDF.js version: 2.4.456
• Is a browser extension: No

Steps to reproduce the problem:

1. Using credit-react-app to create a react project https://github.com/facebook/create-react-app npm init react-app my-app
2. Install pdfjs-dist package npm install pdfjs-dist --save
3. Import package and copy example code to App.js (https://github.com/mozilla/pdf.js/blob/master/examples/node/getinfo.js https://mozilla.github.io/pdf.js/examples/index.html#interactive-examples for prev/next example)

import pdfjsLib from 'pdfjs-dist/es5/build/pdf.js';
...
pdfjsLib.GlobalWorkerOptions.workerSrc = '../node_modules/pdfjs-dist/build/pdf.worker.js';
...
pdfjsLib.getDocument(url);

1. Run react project yarn start
2. Console shows error

Uncaught SyntaxError: Unexpected token '<' pdf.js:11915 
Uncaught (in promise) Error: Setting up fake worker failed: "Cannot read property 'WorkerMessageHandler' of undefined".
    at pdf.js:11915

What is the expected behavior? (add screenshot) Worker is setting up correctly.

What went wrong? (add screenshot) pdfjsWorker does not exist in window object, which causes ‘WorkerMessageHandler’ of undefined issue. The switch statement started with case 0 -> case 3 -> case 6 -> case 8, ended up with catch() in _setupFakeWorker()

function setupFakeWorkerGlobal() {
...
case 8:
   return _context.abrupt("return", window.pdfjsWorker.WorkerMessageHandler);
...
}

Link to a viewer (if hosted on a site other than mozilla.github.io/pdf.js or as Firefox/Chrome extension): (Trying to push code to my github, but reproducing the issue is very straight forward if following the steps. all functions are the same as example code. renderPage() etc.)

[yummyelin]

Hi, I don’t know why, but looks like copy pdf.worker.js to my project’s output folder, or use cdn worker will make the magic happen. Using the one from node_modules/ doesn’t work.

 // pdfjsLib.GlobalWorkerOptions.workerSrc = '../node_modules/pdfjs-dist/build/pdf.worker.js';
  pdfjsLib.GlobalWorkerOptions.workerSrc = `//cdnjs.cloudflare.com/ajax/libs/pdf.js/2.1.266/pdf.worker.js`;

https://github.com/wojtekmaj/react-pdf#create-react-app

[Snuffleupagus]

Given that we know nothing about React here, is it meaningful to keep this issue open when we unfortunately cannot help? /cc @timvandermeij