remove legacy mdx 1 feature documentation

MIGRATION.md

@@ -4,7 +4,7 @@
   - [Implicit actions can not be used during rendering (for example in the play function)](#implicit-actions-can-not-be-used-during-rendering-for-example-in-the-play-function)
   - [MDX related changes](#mdx-related-changes)
     - [MDX is upgraded to v3](#mdx-is-upgraded-to-v3)
-    - [Dropping support for \*.stories.mdx (CSF in MDX) format](#dropping-support-for-storiesmdx-csf-in-mdx-format)
+    - [Dropping support for \*.stories.mdx (CSF in MDX) format and MDX1 support](#dropping-support-for-storiesmdx-csf-in-mdx-format-and-mdx1-support)
     - [Dropping support for id, name and story in Story block](#dropping-support-for-id-name-and-story-in-story-block)
   - [Core changes](#core-changes)
     - [Dropping support for Node.js 16](#dropping-support-for-nodejs-16)
@@ -390,10 +390,12 @@ To summarize:
 
 Storybook now uses MDX3 under the hood. This change contains many improvements and a few small breaking changes that probably won't affect you. However we recommend checking the [migration notes from MDX here](https://mdxjs.com/blog/v3/).
 
-#### Dropping support for *.stories.mdx (CSF in MDX) format
+#### Dropping support for *.stories.mdx (CSF in MDX) format and MDX1 support
 
 In Storybook 7, we deprecated the ability of using MDX both for documentation and for defining stories in the same .stories.mdx file. It is now removed, and Storybook won't support .stories.mdx files anymore. We provide migration scripts to help you onto the new format.
 
+If you were using the [legacy MDX1 format](#legacy-mdx1-support), you will have to remove the `legacyMdx1` main.js feature flag and the `@storybook/mdx1-csf` package.
+
 Alongside with this change, the `jsxOptions` configuration was removed as it is not used anymore.
 
 [More info here](https://storybook.js.org/docs/migration-guide#storiesmdx-to-mdxcsf).

docs/api/main-config-features.md

@@ -54,23 +54,6 @@ Apply decorators from preview.js before decorators from addons or frameworks. [M
 
 <!-- prettier-ignore-end -->
 
-## `legacyMdx1`
-
-Type: `boolean`
-
-Enables support for MDX version 1 as a fallback. Requires [@storybook/mdx1-csf](https://github.com/storybookjs/mdx1-csf) to be installed.
-
-<!-- prettier-ignore-start -->
-
-<CodeSnippets
-  paths={[
-    'common/main-config-features-legacy-mdx-1.js.mdx',
-    'common/main-config-features-legacy-mdx-1.ts.mdx',
-  ]}
-/>
-
-<!-- prettier-ignore-end -->
-
 ## `storyStoreV7`
 
 Type: `boolean`

docs/configure/index.md

@@ -56,7 +56,6 @@ Additionally, you can also provide additional feature flags to your Storybook co
 | --------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
 | `storyStoreV7`        | Configures Storybook to load stories [on demand](#on-demand-story-loading), rather than during boot up (defaults to `true` as of `v7.0`) <br/> `features: { storyStoreV7: true }`             |
 | `buildStoriesJson`    | Generates `index.json` and `stories.json` files to help story loading with the on-demand mode (defaults to `true` when `storyStoreV7` is `true`) <br/> `features: { buildStoriesJson: true }` |
-| `legacyMdx1`          | Enables support for MDX version 1 as a fallback. Requires [`@storybook/mdx1-csf`](https://github.com/storybookjs/mdx1-csf) <br/> `features: { legacyMdx1: true }`                             |
 
 ## Configure story loading
 

docs/migration-guide.md

@@ -94,26 +94,6 @@ This shows the errors visually in your editor, which speeds things up a lot. Her
 
 ![MDX errors showing in VS Code](./assets/mdx-vs-code-extension-errors.gif)
 
-#### MDX1 as fallback
-
-If, for some reason, you are unable to get MDX2 working, we’ve implemented legacy MDX1 support as a last resort. MDX1 is deprecated and opt-in, and we recommend against it unless you really need it.
-
-To use MDX1:
-
-1. Install `@storybook/mdx1-csf` as a dev dependency
-2. Add the `legacyMdx1` feature flag to your `.storybook/main.js`:
-
-<!-- prettier-ignore-start -->
-
-<CodeSnippets
-  paths={[
-    'common/main-config-features-legacy-mdx-1.js.mdx',
-    'common/main-config-features-legacy-mdx-1.ts.mdx'
-  ]}
-/>
-
-<!-- prettier-ignore-end -->
-
 ### storiesOf support discontinued by default
 
 If you use Storybook’s legacy `storiesOf` API, it is no longer supported by default in Storybook 7.

scripts/verdaccio.yaml

@@ -87,14 +87,6 @@ packages:
     access: $all
     publish: $all
     proxy: npmjs
-  '@storybook/mdx1-csf':
-    access: $all
-    publish: $all
-    proxy: npmjs
-  '@storybook/mdx2-csf':
-    access: $all
-    publish: $all
-    proxy: npmjs
   '@storybook/expect':
     access: $all
     publish: $all