Inexplicable Error Message Stopping Progress!

I restarted a basic HTML lesson.

The first lesson: Create an h1 element displaying “Hello World”

I coded: <h1>Hello World</h1>

I clicked the button “Run the Tests” and it returned the following error:
TypeError: t.querySelectorAll(...).forEach is not a function

I tried resetting the code and trying a different lesson, but the result has not changed.

Thank you in advance for any assistance!

Welcome, Lex.

I’ve edited your post for readability. When you enter a code block into a forum post, please precede it with a separate line of three backticks and follow it with a separate line of three backticks to make it easier to read.

Please use the “preformatted text” tool in the editor (</>) to add backticks around text.

See this post to find the backtick on your keyboard.
Note: Backticks are not single quotes.


As for your problem:

  • Frequently, users encounter issues with the challenges for any of these reasons:
    • A browser extension has access to (Disable all extensions with access; they interfere, and freeCodeCamp contains no advertisements, so no adblock needed)
    • Outdated browser/Uncommon browser (The recommended browser for the freeCodeCamp curriculum is the latest stable release of Chrome).

For future posts, I recommend you use the Get Help/Ask for Help button on the specific challenge you are having problems with. This will automatically create a forum post in the correct sub-forum, whilst also providing some useful information including your current code. You will have an opportunity to include any extra information in the post before submitting.

Hope this helps