Stylesheet is duplicated on the Index page

[phenomen]

What version of astro are you using?

1.2.3

Are you using an SSR adapter? If so, which one?

None

What package manager are you using?

npm

What operating system are you using?

Windows, Linux

Describe the Bug

After build, stylesheet is placed in the head and in the middle of the body.

On Stackblitz it's reproducible on the index page (/) with

npm build
npm preview

Link to Minimal Reproducible Example

https://stackblitz.com/edit/github-xkmtka?file=src/pages/index.mdx

Participation

• [ ] I am willing to submit a pull request for this issue.