I wasnʼt thinking about multiparagraph summaries. But actually, I
realize that your suggestion in response would work with only one small
change to a variable in ox-html.
Yes, the proposal though supports these 2 things specific to details element:
1. Detecting "open" attribute via "#+attr_html: open".
2. Adding a wrapper <p class="details"> tag around the details portion following the <summary> tag. Useful if user wants to set CSS rules for "details .details".
Assuming there are no objections, we could make this tweak to
‘org-html-html5-elements’ in org core.
I don't mind adding that to ox-html. Just that the details disclosure implementation will be /slightly/ incomplete, but still very functional.
I think “syntactic sugar” like
your original proposal could be implemented as a before-parsing-hook
that transforms the --- into the above syntax.
+1
PS Once upon a time, I created ox-extras in contrib as a home for little
snippets like this hypothetical before-parsing-hook. It never really
took off, but maybe itʼs just biding its time...
Sure thing :)