Basic CSS: Improve Compatibility with Browser Fallbacks tests fail on Firefox latest version

Describe your problem and how to reproduce it:
My problem is that when doing “Basic CSS: Improve Compatibility with Browser Fallbacks” challenge the test fails despite I’m doing things well.
I’ve verified that in Chrome it works properly.
Here is the code:

  :root {
    --red-color: red;
  .red-box {
    backgorund: red;
    background: var(--red-color);
    height: 200px;
<div class="red-box"></div>

Add a Link to the page with the problem:

Tell us about your browser and operating system:

  • Browser Name: Firefox Quantum
  • Browser Version: 68.11.0esr (64-bit)
  • Operating System: Windows 10 Home, version 1903, operative system version 18362.959.

If possible, add a screenshot here (you can drag and drop, png, jpg, gif, etc. in this box):

You can see that test fails but the code is correct

I’ve already made an issue on GitHub and they answered:

Please use our forum for debugging the code of your projects. If the forum members determine there is nothing wrong with your code, you can request this issue to be reopened. GitHub issues are meant for reporting bugs and not troubleshooting the code in your projects.

Thank you for understanding.

You have a typo on the above line.


Thanks @RandellDawson.