code: @Override
  	public void apply(final App app, final Page sourcePage, final Page newPage) throws FrameworkException {
  
  		// do not delete synced nodes (nodes that are shared between multiple pages)
  		if (!existingNode.isSynced()) {
  
  			// remove node from parent, do not simply delete it
  			final Node parent = existingNode.getParentNode();
  			if (parent != null) {
  
  				parent.removeChild(existingNode);
  			}
  
  			app.delete(existingNode);
  		}
  	}
docs: ----- interface InvertibleModificationOperation -----