When I edit the code in a TextArea using CodeMirror how to reflect this into another textarea with js or jQuery

Question

The App: I have a textarea element in my page. It is transformed using CodeMirror, because I need to indent and highlight html code withing it. Pic is in the li

Answer 1

This works work CodeMirror 5.22.0:

CodeMirror.fromTextArea(document.getElementById('grammar'), {
    lineNumbers: true,
    mode: 'pegjs',
}).on('change', editor => {
    console.log(editor.getValue());
});