Yes, I did the foldable thingies in https://wordsandbuttons.online/programmers_guide_to_polynomials_and_splines.html https://wordsandbuttons.online/programmers_

Yes, I did the foldable thingies in https://wordsandbuttons.online/programmers_guide_to_polynomials_and_splines.html https://wordsandbuttons.online/programmers_guide_to_polynomi... and https://wordsandbuttons.online/if_i_were_to_invent_a_programming_language_for_the_21st_century.html https://wordsandbuttons.online/if_i_were_to_invent_a_program... But not on this page. I thought that the arrows are a bit noisy. I can still add this "toggle back" feature here if you want.