Katex and Mathjax in Nextjs

[edward1127]

Summary

Given https://codesandbox.io/s/katex-mhchem-wl7q64 and https://stackblitz.com/edit/nextjs-xvqkxb?file=pages/index.js clearly rehype-katex clearly can access the mhchem context.
https://stackblitz.com/edit/stackblitz-starters-ueq3rk?file=src%2FApp.tsx Shows that everything works fine in React.
With the smaller reproducible examples it's increasingly looking like it works up to the point next it added to the picture.
Which implies something next is doing is likely the root cause.

Combined with remarkjs/remark-math#80 it leads me to believe something about Next SSR messes with Katex and Mathjax.
Remark and MDX just happen to also be in the dependency tree, but seem to be unrelated to the issues being seen.

Originally posted by @ChristianMurphy in remarkjs/remark-math#81 (comment)

I try to use CSR with Next https://stackblitz.com/edit/nextjs-ftepsg?file=pages%2Findex.js, and it's still not working. I believe somehow nextjs cannot get the context of import "katex/dist/contrib/mhchem";

Additional information

No response

Example

vanilla js
https://codesandbox.io/s/katex-mhchem-wl7q64
react
https://stackblitz.com/edit/stackblitz-starters-ueq3rk?file=src%2FApp.tsx
next
https://stackblitz.com/edit/nextjs-xvqkxb?file=pages/index.js
next csr
https://stackblitz.com/edit/nextjs-ftepsg?file=pages%2Findex.js