title: Storybook - no stories showing up in typescript project with custom webpack / babel
body: <p>I am trying to set up Storybook in a project.  My project is runing on react@^16, and I'm using typescript, with a custom babel and webpack setup for development and build.  To set up storybook, I did</p>
  <pre class="lang-js prettyprint-override"><code>npx sb init
  </code></pre>
  <p>This installs everything needed. It puts a <code>.storybook</code> folder in the root folder, and a <code>stories</code> folder in my <code>src</code> folder with some prefab components and stories in <code>tsx</code> format (which is what I want):</p>
  <p><a href="https://i.stack.imgur.com/oJjle.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/oJjle.png" alt="enter image description here" /></a></p>
  <p><a href="https://i.stack.imgur.com/zcTb9.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/zcTb9.png" alt="enter image description here" /></a></p>
  <p>The <code>.storybook/main.js</code> file seems fine:</p>
  <pre class="lang-js prettyprint-override"><code>module.exports = {
    &quot;stories&quot;: [
      &quot;../src/**/*.stories.mdx&quot;,
      &quot;../src/**/*.stories.@(js|jsx|ts|tsx)&quot;
    ],
    &quot;addons&quot;: [
      &quot;@storybook/addon-links&quot;,
      &quot;@storybook/addon-essentials&quot;
    ]
  }
  </code></pre>
  <p>And the average .stories.js file automatically installed by <code>npx sb init</code> also seems fine:</p>
  <pre class="lang-js prettyprint-override"><code>import React from 'react';
  // also exported from '@storybook/react' if you can deal with breaking changes in 6.1
  import { Story, Meta } from '@storybook/react/types-6-0';
  
  import { Header, HeaderProps } from './Header';
  
  export default {
    title: 'Example/Header',
    component: Header,
  } as Meta;
  
  const Template: Story&lt;HeaderProps&gt; = (args) =&gt; &lt;Header {...args} /&gt;;
  
  export const LoggedIn = Template.bind({});
  LoggedIn.args = {
    user: {},
  };
  
  export const LoggedOut = Template.bind({});
  LoggedOut.args = {};
  </code></pre>
  <p>But when I run <code>npm run storybook</code>, the storybook landing page has no stories.  Even though it had installed some default stories to start playing with.  It says:</p>
  <pre><code>Oh no! Your Storybook is empty. Possible reasons why:
  The glob specified in main.js isn't correct.
  No stories are defined in your story files.
  </code></pre>
  <p>As requested, <a href="https://github.com/slutske22/20-maps" rel="nofollow noreferrer">here</a> is a link to the repo so you can dig a bit deeper into the structure, weback config, etc.  Note I have <em>not</em> committed the <code>npx sb init</code> changes yet, so you won't see the files there, only my starting point just before running the <code>sb init</code>.</p>
  <p>I haven't had any issues getting <code>npx sb init</code> to work with a standard create-react-app, but with my custom webpack build and typescript, its just empty.  What's going wrong?</p>
  <h3>Edit: Additional detail</h3>
  <p>I realize that just running <code>npx sb init</code>, then <code>npm run storybook</code> throws this error:</p>
  <pre class="lang-js prettyprint-override"><code>ERROR in ./.storybook/preview.js-generated-config-entry.js
  Module not found: Error: Can't resolve 'core-js/modules/es.array.filter'
  </code></pre>
  <p>Based on <a href="https://github.com/storybookjs/storybook/issues/11255" rel="nofollow noreferrer">this thread</a>, installing <code>core-js@3</code> solves the problem and storybook runs, though with no stories.</p>