message: Turn off the intend guides in the Ace text viewer.
diff: @@ -158,6 +158,7 @@ export class TextViewer extends ViewerElement implements Commandable, AcceptsKey
  const aceRenderer = new TerminalRenderer(containerDiv);
  aceRenderer.setShowGutter(false);
  aceRenderer.setShowLineNumbers(false);
  + aceRenderer.setDisplayIndentGuides(false);
  this._aceEditor = new ExtratermAceEditor(aceRenderer, this._aceEditSession);
  