title: Listen to event fired when the content has changed in CKEditor 5
body: <p>How can I listen to the "input" event in <strong>ckeditor5</strong> ? I would like to be able to use <code>Observables</code> like this:</p>
  
  <pre><code>Observable.fromEvent(this.editor, "input").debounceTime(250).subscribe(() =&gt; {});
  </code></pre>
  
  <p>So far, I've been able to listen to some events like this:</p>
  
  <pre><code>Observable.fromEvent(this.editor.editing.view, 'selectionChangeDone').subscribe(() =&gt; { });
  </code></pre>
  
  <p>But I don't find the name of the event that would be fired as soon as data changed in the editor. I tried "change" but it only fires when the editor get or lost focus.</p>