Add expandable blocks to the Knowledge Base

To keep the logical flow of a page easy to follow it is useful to be able to hide details, perhaps a code block, or a detailed explanation

The wiki ends up with long pages which are hard to read

I would like to be able to put text or any other items on the page into a box which is marked as expandable. On the published wiki, the user sees some (user-defined) text such as 'Click to Expand' or 'See source code' or 'Click to see Further Details'. Clicking on this opens or closes the expanded information