Just like callouts can enable folding with default open or default closed?
I would like to have some sections/headings folded by default (unless editing). Something like ##- Heading for a pre-folded heading?
The section I want to hide contains checkboxes, tasks, and some ^anchor anchors, so using a callout to hide the content effectively disables that functionality.
Obsidian is pretty good about remembering what you’ve folded. If that isn’t good enough, you’ll need to look at plugins. I think the Creases plugin might do what you want but I don’t remember for sure.