Why is the component eating the div element, React?

Question

JavaScript

Good afternoon! Please help me figure out why this is the case with server side rendering in React?
It turns out a different render of the component in such situations

render() {
    return (
      <div className="header hgg" onClick={this.handleClick}> //  в этом случае все нормально
        <div>
          <h1>HEADER!!!!!</h1>
        </div>
      </div>
    )
  }

here is the problem.

render() {
    return (
      <div className="header hgg" onClick={this.handleClick}> .// блок не выводится, хотя видно мигание, появляется и исчезает
        <h1>HEADER!!!!!</h1>
      </div>
    )
  }

Who knows please explain why?
Thank you!

Answer 1

I posted a demo here on react 16, everything is fine, can you make a demo where there is a problem?
What versions of the libraries?