I’ve tried to create the minimalist version of this with Revise.js. The main surface area is a custom element called a `<content-area>`. The OverType library you linked to uses a time-old technique where you essentially put a duplicate copy of the content over a `<textarea>` to highlight it but this doesn’t really work in mobile and it messes with the selection. I’ve tried to grapple with `contenteditable` directly with my solution, but it does try to use less JavaScript and it does try to be more minimal.

https://github.com/bikeshaving/revise https://revise.js.org https://revise.js.org/blog/introducing-revise/