TiddlyStretch is a TiddlyWiki plugin that allows you to write stretchtext, a form of hypertext where content can be expanded and contracted in place.
Installation and use instructions can be found at https://sobjornstad.github.io/TiddlyStretch/.
You can find a few real examples of stretchtext in use on my Zettelkasten.
Install the TiddlyWiki plugin in the plugins/TiddlyStretch/ subdirectory
directly to your Node.JS wiki
(I like using Peru to manage plugins)
or build it into a TiddlyWiki plugin using the dev instructions
and then install it in your single-file wiki.
TiddlyWiki >=5.1.21 is required.