rsnext/examples/with-filbert/pages/_document.js

import Document from 'next/document'
import { createStylesheet } from '@filbert-js/server-stylesheet'

class MyDocument extends Document {
  static async getInitialProps(ctx) {
    const sheet = createStylesheet()
    const originalRenderPage = ctx.renderPage
    try {
      ctx.renderPage = () =>
        originalRenderPage({
          enhanceApp: (App) => {
            return (props) => {
              return sheet.collectStyles(<App {...props} />)
            }
          },
        })
      const initialProps = await Document.getInitialProps(ctx)

      const styleTags = sheet.getReactElements()
      return {
        ...initialProps,
        styles: (
          <>
            {styleTags}
            {initialProps.styles}
          </>
        ),
      }
    } finally {
    }
  }
}

export default MyDocument