How to disable undo button

On undo/redo events https://grapesjs.com/docs/api/editor.html#general you can use Undo Manager APIs https://grapesjs.com/docs/api/undo_manager.html

@artf If the undo event needs to be triggered to present it's data, then how can we render or disable the undo/redo btns? Out of the box the Undo/Redo buttons will clear out an entire template if the undo/redo event hasn't tracked anything. I am trying to conditionally render the undo/redo buttons based on there being anything to undo/redo. I am having trouble with the general event "Update". The Update event never seems to be triggered. Can you provide a little more context?

this.editor.on('update', () => {
      const pnm = this.editor.Panels;
      const um = this.editor.UndoManager;
      const optsPanel = pnm.getPanel('options');
      if (um.hasUndo().length > 0) {
        optsPanel.get('buttons').add({
          id: 'undo',
          className: 'fa fa-undo',
          command: 'undo',
          attributes: { title: 'undo' },
        });
      }
    });

If the undo event needs to be triggered to present it's data, then how can we render or disable the undo/redo btns?

??? You can use the Undo Manager APIs wherever you want, I didn't say you can use it only after undo/redo events.

The Update event never seems to be triggered

The update event was added in https://github.com/artf/grapesjs/releases/tag/v0.14.55