import innerText from 'react-innertext';
innerText(
  <div>
    Hello <strong>world</strong>!
    I am <span children={3} /> years old!
  </div>
) // 'Hello world! I am 3 years old!'

const innerText = require('react-innertext');
innerText(
  <div>
    Hello <strong>world</strong>!
    I am <span children={3} /> years old!
  </div>
) // 'Hello world! I am 3 years old!'

function MyTableHeader() {
  return (
    <thead>
      <tr>
        <MyTableHeaderCell>
          <b>Username</b>
          <SortButton />
        </MyTableHeaderCell>
      </tr>
    </thead>
  );
}

// title="Username"
function MyTableHeaderCell({ children }) {
  return (
    <th
      children={children}
      title={innerText(children)}
    />
  );
}