[Question] about "._owner.alternate"

It seems that in react@16 every React element children contains cyclic property ._owner.alternate.alternate.alternate.alternate....

So it is easy to cause "Maximum call stack exceeded" error when developer compares props.children in deep way(like deep-equal).

This caused bugs for community libraries like react-helmet:
https://github.com/nfl/react-helmet/issues/441

I am extremely curious about:
Why React has _owner.alternate, and what it stands for?
As it is named as “_owner”, could it be better if we make “owner” not enumerable?

I tried to search source code and but still can’t find any clue.

Thanks in advance.

未指定文件或测试。首先追踪创建元素子节点和 _owner.alternate 链的 React 16 源代码，然后查看链接的 react-helmet issue 441。完成的标准是记录 _owner.alternate 所表示的内容，并确定 enumerable owner 问题是否需要记录在案的更改。