Hello! I am a new Quarto user and am trying to follow the tutorial. When I get to the code-fold option, I run into the following error: 
I'm not sure, what I'm doing wrong. I think I am following the example exactly. Thanks!

Validation of YAML front matter failed.
In file computations.qmd
(line 4, columns 3--7) Key html has empty value but it must instead be an object
3: format:
4:   html: 
          
5:   code-fold: true
In file computations.qmd
(line 5, columns 14--17) Key format has value true, which must be no possible value
4:   html: 
5:   code-fold: true
                ~~~
6: ---
Render failed due to invalid YAML.


2022-08-14T10:09:55Z
annier01
closed
Quarto -Tutorial Error on Code-Fold
https://github.com/quarto-dev/quarto-cli/issues/1861