Add support for collapsing page content under headings

[greatislander]

Is your feature request related to a problem? Please describe.

It's been requested that some pages load with their content collapsed under the page headers.

Describe the solution you'd like

We should handle this using a parse transform. To be determined:

1. Which heading levels should collapse?
2. What types of content should this apply to?
3. What should the collapse/expand behaviour be? Can more than one section be expanded at once? Same behaviour as seen here? https://wecount.inclusivedesign.ca/advisory-panel/

Describe alternatives you've considered

Not applicable.

Additional context

Not applicable.

[chosww]

Hey @carenwatkins, would you be able to provide answers to the 3 questions in the description?

[carenwatkins]

@chosww @greatislander

Which heading levels should collapse?
Heading 2

What types of content should this apply to?
Can we choose to apply collapse / expand H2s on any content? For example, there may be an initiative page (like FWD) with a lot of content and could benefit from users having the option to collapse content (it can be overwhelming to have all that content on the page at once).

What should the collapse/expand behaviour be? Can more than one section be expanded at once?
People coming to the page should have control over what they want to expand and collapse within the content, therefore, each H2 can be actioned independently AND there should be global expand / collapse buttons as well. See sketch attached.

This task isn’t urgent but let me know what you think. Is this something that is doable in a reasonable time frame?