Form field is read-only. I did the code twice from scratch and has same problem

[durrantm]

Browser gives:

react-dom.js:18112 Warning: Failed form propType: You provided a value prop to a form field without an onChange handler. This will render a read-only field. If the field should be mutable use defaultValue. Otherwise, set either onChange or readOnly. Check the render method of Editor.

and then I can't change the text in the textarea to make the word counter work.

[durrantm]

btw kindle book is also missing the chapter numbers on the pages which is frustrating.

[durrantm]

See my code at https://github.com/durrantm/reactBookIssue