Problem with sample program in Async Generators and Iterators article

In Plunker, following Open in Sandbox link, code provided under "An example of use (shows commit authors in console):" doesn't work (because it doesn't include fetchCommits function).

Console shows error:

(index):9 Uncaught (in promise) ReferenceError: fetchCommits is not defined
(index):9 Uncaught (in promise) ReferenceError: fetchCommits is not defined
    at (index):9
    at (index):18

Running the code directly from the run link in article also doesn't work. Gives error:

holder-2.2.min.js:10 Uncaught TypeError: Cannot read property 'appendChild' of undefined
    at Object.e.run (holder-2.2.min.js:10)
    at holder-2.2.min.js:10
    at XMLDocument.h (holder-2.2.min.js:10)

Code in question:

(async () => {

  let count = 0;

  for await (const commit of fetchCommits('javascript-tutorial/en.javascript.info')) {

    console.log(commit.author.login);

    if (++count == 100) { // let's stop at 100 commits
      break;
    }
  }

})();

Abre el artículo Async Generators and Iterators e inspecciona el snippet “An example of use”, junto con sus enlaces Open in Sandbox y run. Reproduce los errores indicados y, después, actualiza el ejemplo o los samples enlazados para que fetchCommits esté disponible y el código se ejecute sin el error de Holder.