We have completed this project. The Guidelines have been updated, and we have fixed most errors in mdn/content.

There is always more to be done, so feel free to submit PRs!

Thank you all for your help. It was an amazing journey! From this vivid discussion to the 50+ PRs and the code guideline revisions.

At some points, we'll want to fix code outside the mdn/content repository, but this will be for a separate project.

Thank you all. You rock! 🎉