title: Gatsby v2 site does not load CSS properly
body: <p>In my dev environment the site looks as expected, however when I run gatsby build my CSS does not display properly. If I manually navigate to another page then the CSS displays as expected.</p>
  
  <p>There are no errors but I do get this warning: </p>
  
  <blockquote>
    <p>The resource
    <a href="http://localhost:9000/static/d/520/path---offline-plugin-app-shell-fallback-a-30-c5a-NZuapzHg3X9TaN1iIixfv1W23E.json" rel="nofollow noreferrer">http://localhost:9000/static/d/520/path---offline-plugin-app-shell-fallback-a-30-c5a-NZuapzHg3X9TaN1iIixfv1W23E.json</a>
    was preloaded using link preload but not used within a few seconds
    from the window's load event. Please make sure it has an appropriate
    <code>as</code> value and it is preloaded intentionally.</p>
  </blockquote>
  
  <p>When I inspect that file it shows:</p>
  
  <pre><code>{"pageContext":{}}
  </code></pre>
  
  <p>The fact that that object is empty is my issue I assume. I have tried disabling the service worker but that only made the issue worse.</p>
  
  <p>I've also tried </p>
  
  <ul>
  <li>forcing a build and disabling the cache on netlify,</li>
  <li>deleting npm and package.json files and then running npm build,</li>
  </ul>
  
  <p>but no luck so far.</p>