The setting collapse="true" does not work in a revealjs presentation.
See code below:
:::{.callout-caution collapse="true"}
## Expand To Learn About Collapse
This is an example of a 'folded' caution callout that can be expanded by the user. You can use `collapse="true"` to collapse it by default or `collapse="false"` to make a collapsible callout that is expanded by default.
:::
The setting collapse="true" does not work in a revealjs presentation.
See code below: