there bug in code react jsx

There are some problems with the react jsx

The following code

```js
import React from "react";
import ReactDOM from "react-dom";

let el = (
    <div>
        <h1>hello</h1>
        <label htmlFor="username">username</label>
        <input type="text" id="username"/>
    </div>
);

ReactDOM.render(el, window.root);
```
