title: Gatsby build error (webpack related maybe)
body: <p>I made a site with gatsby (npm init gatsby) and added some components and was working fine then:</p>
  <p>I run npm run develop (after running it before fine) and get this:</p>
  <pre><code>failed Building development bundle - 13.532s
  ERROR in ./.cache/app.js
  Module build failed (from ./node_modules/@pmmmwh/react-refresh-webpack-plugin/loader/index.js):
  Error: You must provide the URL of lib/mappings.wasm by calling SourceMapConsumer.initialize({ 'lib/mappings.wasm': ... }) before using
  SourceMapConsumer
  
  ERROR in ./.cache/polyfill-entry.js
  Module build failed (from ./node_modules/@pmmmwh/react-refresh-webpack-plugin/loader/index.js):
  Error: You must provide the URL of lib/mappings.wasm by calling SourceMapConsumer.initialize({ 'lib/mappings.wasm': ... }) before using
  SourceMapConsumer
  </code></pre>
  <p>What causes this error and how can I fix this? I'm baffled. Tried with fresh new site and does the same thing.</p>
  <p>I upgraded to latest version of node so maybe this has something to do with it. Can anyone help?</p>