ove dragged element from its old location, if checkbox is checked
          if (document.getElementById('removeCheckBox').checked)
            dragged.parentNode.removeChild(dragged);
        }

        // If we were using drag data, we could get it here, ie:
        // const data = event.dataTransfer.getData('text');
      },
      false
    );

    // this is called on a stationary node or link during an external drag-and-drop into a Diagram
    function onHighlight(part) {
      // may be null
      cons