code: function onModEnter(
      event: *,
      change: Change,
      editor: *,
      opts: Options
  ): void | Change {
      const { value } = change;
      if (!value.isCollapsed) {
          return undefined;
      }
  
      event.preventDefault();
  
      const exitBlock = Block.create({
          type: opts.exitBlockType,
          nodes: [Text.create('')]
      });
  
      const table = TablePosition.create(opts, value.document, value.startKey)
          .table;
      const tableParent = value.document.getParent(table.key);
      const insertionIndex = tableParent.nodes.indexOf(table) + 1;
  
      return change
          .insertNodeByKey(tableParent.key, insertionIndex, exitBlock)
          .collapseToStartOf(exitBlock);
  }
docs: Exit the current table, by inserting a default block after the table.