Clean up plugins

packages/next/build/plugins/collect-plugins.ts

@@ -24,9 +24,6 @@ export const VALID_MIDDLEWARE = [
   'on-error-client',
   'on-error-server',
   'babel-preset-build',
-  'unstable-post-hydration',
-  'unstable-get-styles-server',
-  'unstable-enhance-app-server',
 ]
 
 type ENV_OPTIONS = { [name: string]: string }

packages/next/client/index.js

@@ -79,20 +79,6 @@ class Container extends React.Component {
   componentDidMount() {
     this.scrollToHash()
 
-    if (process.env.__NEXT_PLUGINS) {
-      // eslint-disable-next-line
-      import('next-plugin-loader?middleware=unstable-post-hydration!')
-        .then((mod) => {
-          return mod.default()
-        })
-        .catch((postHydrationErr) => {
-          console.error(
-            'Error calling post-hydration for plugins',
-            postHydrationErr
-          )
-        })
-    }
-
     // We need to replace the router state if:
     // - the page was (auto) exported and has a query string or search (hash)
     // - it was auto exported and is a dynamic route (to provide params)

packages/next/pages/_document.tsx

@@ -56,30 +56,12 @@ export default class Document<P = {}> extends Component<DocumentProps & P> {
   static async getInitialProps(
     ctx: DocumentContext
   ): Promise<DocumentInitialProps> {
-    const enhancers = process.env.__NEXT_PLUGINS
-      ? await import(
-          // @ts-ignore loader syntax
-          'next-plugin-loader?middleware=unstable-enhance-app-server!'
-        ).then((mod) => mod.default(ctx))
-      : []
-
     const enhanceApp = (App: any) => {
-      for (const enhancer of enhancers) {
-        App = enhancer(App)
-      }
       return (props: any) => <App {...props} />
     }
 
     const { html, head } = await ctx.renderPage({ enhanceApp })
-    const styles = [
-      ...flush(),
-      ...(process.env.__NEXT_PLUGINS
-        ? await import(
-            // @ts-ignore loader syntax
-            'next-plugin-loader?middleware=unstable-get-styles-server!'
-          ).then((mod) => mod.default(ctx))
-        : []),
-    ]
+    const styles = [...flush()]
     return { html, head, styles }
   }