title: Ace editor pressing enter key does not add a newline
body: <p>No newline is inserted when pressing the enter key in the editor field of an ace editor instance. Nothing happens.</p>
  
  <p>Example initiation:</p>
  
  <pre><code>let codeEditor = ace.edit('someElementId', {
      minLines: 6,
      maxLines: 20,
      showLineNumbers: false,
      readOnly: false,
      newLineMode: 'auto',
  });
  codeEditor.setTheme('ace/theme/chrome');
  codeEditor.session.setMode('ace/mode/json');
  </code></pre>