title: Alternative for getServerSideProps within _app.tsx
body: <p>I've got some data that multiple pages within my app use. Since the fetch time is atrocious, I'd like to fetch that data when someone loads the site, and then pass that data off to multiple different pages to render in different ways.</p>
  <p>My understanding from <a href="https://stackoverflow.com/questions/70623677/getserversideprops-in-app-tsx-in-next-js">this question</a> is that you aren't able to use getServerSideProps within the <code>_app.tsx</code>. What is the standard for propagating props across your app for NextJS? My guess was to <code>useEffect</code> in the <code>_app.tsx</code>, but that has led to many issues where the data isn't initialized and never updates.</p>
  <p>some napkin-code for context</p>
  <pre><code>// _app.tsx
  function CustomApp({ Component, pageProps }: AppProps) {
    const [data, setData] = useState&lt;DataPoint[]&gt;([])
  
    useEffect(() =&gt; {
      getMyData.then(data =&gt; setData(data))
    }, [])
  
    return (
      &lt;Component {...pageProps} initialData={data}/&gt;
    )
  }
  
  
  // index.tsx
  export function Index({initialData}) {
    const [data, setData] = useState(initialData)
  
    return (
      &lt;Graph {...data} /&gt;
    )
  }
  
  // anotherPage/index.tsx
  export function AnotherPage({initialData}) {
    const [data, setData] = useState(initialData)
  
    return (
      &lt;Table {...data}&gt;
    )
  }
  </code></pre>