title: Next.js no longer pre-generates page HTML
body: <p>I'm building a Jamstack application with Next.js and at some point over the past month or so, the pages stopped pre-generating the HTML (the pages hydrate just fine on load, so I didn't notice when this happened).</p>
  <p>Using the world's simplest component in the <code>pages</code> directory:</p>
  <pre class="lang-js prettyprint-override"><code>const Test = () =&gt; {
    return &lt;h1&gt;Hello worm&lt;/h1&gt;;
  };
  
  export default Test;
  </code></pre>
  <p>... results in an empty <code>&lt;div id=&quot;__next&quot;&gt;&lt;/div&gt;</code> element in the markup sent to the browser (the same is true when I use <code>props</code>, <code>getStaticPaths()</code> or <code>getStaticProps()</code>).</p>
  <p>I'm aware that some Redux packages can cause this behaviour, but I'm not using Redux. My <code>package.json</code> looks like this:</p>
  <pre class="lang-js prettyprint-override"><code>{
    &quot;name&quot;: &quot;sprintwell-takeshape&quot;,
    &quot;version&quot;: &quot;0.1.0&quot;,
    &quot;private&quot;: true,
    &quot;scripts&quot;: {
      &quot;dev&quot;: &quot;next dev&quot;,
      &quot;build&quot;: &quot;next build&quot;,
      &quot;start&quot;: &quot;next start&quot;
    },
    &quot;dependencies&quot;: {
      &quot;@takeshape/routing&quot;: &quot;^7.38.2&quot;,
      &quot;isomorphic-fetch&quot;: &quot;^3.0.0&quot;,
      &quot;next&quot;: &quot;^10.2.3&quot;,
      &quot;next-pwa&quot;: &quot;^5.2.23&quot;,
      &quot;react&quot;: &quot;17.0.2&quot;,
      &quot;react-dom&quot;: &quot;17.0.2&quot;,
      &quot;react-markdown&quot;: &quot;^6.0.2&quot;,
      &quot;sass&quot;: &quot;^1.34.1&quot;,
      &quot;shopify-buy&quot;: &quot;^2.11.0&quot;
    }
  }
  </code></pre>
  <p>(Edit)
  Just to add to the confusion, when I do a build, the results page implies that the pages built <em>do</em> have pre-generated HTML:</p>
  <pre><code>Page                                                           Size     First Load JS
  ┌ ● /                                                          732 B           149 kB
  ├   /_app                                                      0 B            83.3 kB
  ├ ● /[slug]                                                    910 B           149 kB
  ├   ├ /guarantee
  ├   ├ /privacy-policy
  ├   ├ /terms
  ├   └ [+7 more paths]
  ├ ○ /404                                                       3.74 kB        87.1 kB
  ├ λ /api/add-email                                             0 B            83.3 kB
  ├ ● /collections (ISR: 86400 Seconds)                          1.59 kB         149 kB
  ├ ● /collections/[slug]                                        1.91 kB         150 kB
  ├   ├ /collections/tea-cosies
  ├   ├ /collections/mp3-players
  ├   ├ /collections/clothing
  ├   └ [+5 more paths]
  ├ ● /products (ISR: 86400 Seconds)                             1.76 kB         150 kB
  ├ ● /products/[slug]                                           2.07 kB         150 kB
  ├   ├ /products/checkerboard-tea-cosy
  ├   ├ /products/fair-isle-cosy
  ├   ├ /products/christmas-cosy
  ├   └ [+27 more paths]
  └ ● /test (ISR: 86400 Seconds)                                 304 B          83.6 kB
  + First Load JS shared by all                                  83.3 kB
    ├ chunks/0999c87ecb7e0a864f9e303ce1593fb7c2a32c6e.bbad1c.js  13.3 kB
    ├ chunks/11100001.b545b5.js                                  13.6 kB
    ├ chunks/framework.f8bd46.js                                 42.1 kB
    ├ chunks/main.fd1a9a.js                                      9.46 kB
    ├ chunks/pages/_app.3df493.js                                4.08 kB
    ├ chunks/webpack.50bee0.js                                   751 B
    └ css/b93e53639e8085f31884.css                               16.5 kB
  </code></pre>
  <p>Can anyone point me in the right direction?</p>