This is a well-behaved what-you-see-is-what-you-mean editor based on contentEditable, with support for collaborative editing and (soon) customizable document models.

There isn't much documentation yet. You can read a bit more about the project, and see demos at the project page.

Here's a rough overview of the source directories (which may go out of date):

src/
  model/      The document model
  transform/  Operations on the document model
  edit/       The editor
  collab/     Collaborative editing module
  inputrules/ Magic input (-- → —) module
  convert/    Document conversion code to and from DOM, HTML, and Markdown
  menu/       Menu UI modules

To try the editor, run

npm install
npm run demo

And point your browser at /checkout/dir/demo/index.html