This is really cool. Bit of an aside: I used to take notes and share code using SubEthaEdit which pioneered this sort of collaborative editing over a decade ago. While it’s now pretty normal to see students taking collaborative notes in classes using Google Docs (and etherpad before it was acquired by Google to improve the experience in Docs), it was astonishing a decade ago. I recall spontaneously loading it up at a…
There is also gobby and infinote that have been around for as long, if not longer. I've used them to great effect to pair removing when teaching simple softEng concepts.