title: React SSR instead of 'getInitialProps' of 'next.js'
body: <p>For improving TTFB (time to the first byte), the 'PageSpeed Insights
  ' suggests using <code>ReactDOMServer.renderToNodeStream()</code>, but I don't know how to implement it.
  I read the <a href="https://reactjs.org/docs/react-dom-server.html#rendertonodestream" rel="nofollow noreferrer">rendertonodestream</a> article, but I don't know how to use it.
  Also, I read the <a href="https://dev.to/marvelouswololo/how-to-server-side-render-react-hydrate-it-on-the-client-and-combine-client-and-server-routes-1a3" rel="nofollow noreferrer">dev.to article</a>, but in my next.js app, there is no webpack.config.js file. If I cannot use react <code>renderToNodeStream</code> with Next.js, how can I cover the effect of <code>renderToNodeStream</code> in Next.js?</p>