You know what, we really need a pure HTML/CSS spoiler/content-warn-collapse HTML tag. It's a pretty common function, though admittedly the layout and structure of such things varies from website to website.
... and the thing it solves: activating JS to open read-mores on toot direct links, is moot when the up-to-date instances require JS to load anything (grump) anyway~.
@Taylor Philomena manages to do it without JavaScript!
We do recall of a method to do this with pure HTML/CSS, for doing drop-down menus, but that barely got any use and JS became so ubiquitous that everyone did it the JS way anyway.