A second throw at the #stretchtext HTML-JS implementation. It now allows text to be folded back!
I dabbled with the <details> element but its functionalities are too boiled-in to be flexible enough for this use. Ended up with custom tags (st) and classes for pairs (m) of visible (c) and hidden (h) or shown (s) elements.
Oh and also, there's a public demo:
https://delyo.be/experiments/stretchtext/







