title: How to pass props to all pages from getInitialProps in Next.js
body: <p>I want to get same props in all pages that I load. I try to do it with <code>_app.js</code> like this:</p>
  <pre class="lang-js prettyprint-override"><code>export default function MyApp({ Component, pageProps }) {
      return &lt;Component {...pageProps} /&gt;
  }
      
  MyApp.getInitialProps = async (appContext) =&gt; {
      return {
          props: {
              testApp: ['1', '2', '3'],
              testApp2: '222'
          }
      }
  }
  </code></pre>
  <p>But it doesn't work. I get an empty object:</p>
  <pre class="lang-js prettyprint-override"><code>const Error = (props) =&gt; {
      console.log(props);
  
      return (
          &lt;div className=&quot;error-page&quot;&gt;
              ...
          &lt;/div&gt;
      )
  }
  </code></pre>
  <p>What did I do wrong?</p>