function remarkMdx(options) {
  const self = this
  const settings = options || emptyOptions
  const data = self.data()

  const micromarkExtensions =
    data.micromarkExtensions || (data.micromarkExtensions = [])
  const fromMarkdownExtensions =
    data.fromMarkdownExtensions || (data.fromMarkdownExtensions = [])
  const toMarkdownExtensions =
    data.toMarkdownExtensions || (data.toMarkdownExtensions = [])

  micromarkExtensions.push(mdxjs(settings))
  fromMarkdownExtensions.push(mdxFromMarkdown())
  toMarkdownExtensions.push(mdxToMarkdown(settings))
}
Add support for MDX (JSX: `<Video id={123} />`, export/imports: `export {x}
from 'y'`; and expressions: `{1 + 1}`).

@this {Processor}
  Processor.
@param {Readonly<Options> | null | undefined} [options]
  Configuration (optional).
@returns {undefined}
  Nothing.