The known issue of lack of compatibility with screen readers and assistive technology completely prevents blind and visually impaired screen reader users from being able to use and participate in the enormous number of online tools and resources that use CodeMirror as their editor.
It would be wonderful if the need for full inclusion and accessibility support could be given priority by the CodeMirror community.
A working example of how this can be done quite successfully can be found here:
https://teachaccess.github.io/tutorial/