message: optimistic regroup
diff: @@ -79,11 +79,11 @@ const nodeDragSourceSpec = (
  }
  : undefined,
  canCancel: (monitor) => monitor.getOperation() === REGROUP_OPERATION,
  - end: (dropResult, monitor, props) => {
  + end: async (dropResult, monitor, props) => {
  if (monitor.didDrop() && dropResult && props && props.element.getParent() !== dropResult) {
  - return moveNodeToGroup(props.element, isNode(dropResult) ? dropResult : null);
  + await moveNodeToGroup(props.element, isNode(dropResult) ? dropResult : null);
  + dropResult.appendChild(props.element);
  }
  - return undefined;
  },
  collect: (monitor) => ({
  dragging: monitor.isDragging(),
  