on a related note to what @Mariano Guerra posted, here’s a little editor library I made using css highlights https://codeberg.org/charlieroberts/teeny

That looks interesting... I have been looking into replacing Ace, the editor I am currently using in my HyperDoc system, by something more in line with HyperDoc's convivial philosophy - and that means most of all something smaller and simpler and more hackable. I'll take a closer look at teeny! BTW, in addition to smaller and simpler, something I am looking for in an editor is the perspective to implement ideas from Bret Victor's Learnable Programming. I can't do that with Ace because Ace itself is impenetrable. Even its documentation is a mess.

thanks! yes i’d like to eventually support annotations like the ones i presented at LIVE in 2018 (https://charlieroberts.github.io/annotationsAndVisualizations/). but i’m also happy with it working relatively simply… to make these types of annotations happen i think the library would have to become considerably more complex, at which point i’m just reinventing the wheel and should use codemirror/monaco/ace etc. part of the beauty of the highlight api is it’s applied directly to the text without altering the dom, so having this library then go and mess with the dom seems inelegant. but i still keep thinking about it :) long story short teeny probably won’t be flexible enough for what you want.

I am well aware that more features and more simplicity hardly ever go well together. It's one of the basic design defects of our universe 😉