code: function onEnter(
      event: *,
      change: Change,
      editor: *,
      opts: Options
  ): void | Change {
      event.preventDefault();
      const { selection, document } = change.value;
      const pos = TablePosition.create(opts, document, selection.startKey);
  
      if (
          !selection.hasFocusAtStartOf(pos.cell) &&
          !selection.hasFocusAtEndOf(pos.cell)
      ) {
          return undefined;
      }
  
      if (event.shiftKey) {
          return change
              .splitBlock()
              .setBlocks({ type: opts.typeContent, data: {} });
      }
  
      return insertRow(opts, change);
  }
docs: Insert a new row when pressing "Enter"