fromId is not defined when using mdx format

Describe the bug Alright, so I have been trying to translate some of my Docz .mdx files to storybook, with version v5.2.0-alpha.4. And so far so good, I get the canvas tab to work, but when I navigate to the docs tab it crashes saying Cannot read property 'fromId' of undefined.

To Reproduce Steps to reproduce the behavior:

1. Install @storybook/react and @storybook/addon-docs to version 5.2.0-alpha.4.

2. Add the following configuration:

.storybook/config.js

import { load } from '@storybook/react';

// load(require.context('../stories', true, /\.stories\.js$/), module);
load(require.context('../stories', true, /\.stories\.mdx$/), module);

.storybook/preset.js

module.exports = ['@storybook/addon-docs/common/preset'];

.storybook/webpack.config.js

const path = require('path');
const createCompiler = require('@storybook/addon-docs/mdx-compiler-plugin');

const babelrc = path.resolve(__dirname, '.babelrc');

module.exports = async ({ config }) => {
  console.log(config.module.rules);
  config.module.rules.push({
    test: /\.mdx$/,
    use: [
      { 
        loader: 'babel-loader',
        options: {
          configFile: babelrc
        }
      },
      {
        loader: '@mdx-js/loader',
        options: {
          compilers: [createCompiler({})],
        },
      },
    ],
  });
  return config;
};

.storybook/addons.js

import '@storybook/addon-docs/register';

.storybook/.babelrc

{
  "presets": [
    "@babel/preset-react"
  ]
}

1. Add a stories.mdx file, let’s say /stories/button.stories.mdx with the following content:

stories/button.stories.mdx

import { Story } from '@storybook/addon-docs/blocks';
import { Button } from '@storybook/react/demo';

export const componentMeta = {
  title: 'MDX|Button',
}

# Hello Docs

Welcome to the future of Storybook!

<Story name="hello">
  <Button >Hello button!</Button>
</Story>

1. Run storybook and navigate to that documentation

Expected behavior The Docs tab open, and shows the documentation

Screenshots

Code snippets You can find them in the reproduce section.

System:

• OS: MacOS
• Device: Macbook Pro 2018
• Browser: chrome
• Framework: react
• Addons: @storybook/addon-docs
• Version: v5.2.0-alpha.4

Additional context I think I have added everything, If more information is needed, I will provide it!

[eden-lane]

I have the same issue in storybook 5.3.14 My main.js file is

module.exports = {
  stories: ['../app/**/*.stories.mdx'],
  addons: [
    {
      name: '@storybook/addon-docs',
      options: {
        configureJSX: true,
      }
    },
    '@storybook/addon-knobs',
    '@storybook/addon-actions',
    '@storybook/addon-links',
  ],
  presets: [
    '@storybook/preset-typescript',
  ],
};

Solved: I forgot to set up DocsPage in .storybook/preview.js

[chrispcode]

Yes, that was the solution! Sorry for losing your time with this guys.