Why is Dynamic Link Variable not interpolated on Link => getServerSideProps

[followbl]

In the below example - if I hit the url directly https://www.example.com/post/abc page works fine (context.params.slug) is fine...but if I navigate from a Next.js link from a feed page as shown below - params (and query) are not interpolated, but returned as [slug], not the abc I'm looking for.

On top of this - this only happens in the production build deployed to vercel - this behavior does not happen in development...

something I'm doing wrong?

Page: https://www.example.com/feed

<Link href="/post/[slug]" as="/post/abc">
  <a>First Post</a>
</Link>

Page: https://www.example.com/post/[slug]

export const getServerSideProps: GetServerSideProps = async (context) => {
  const postData = await fetcher(`/api/${context.params.slug}`, context.req.headers);

  return {
    props: {
      initialData: !!postData ? postData : null,
    },
  };
};

[followbl]

For more context - here is straight from the Vercel deployed logs

[jamesmosier]

Hey @followbl! Does this work as intended if you build/start locally? For me it does, but I just wanted to narrow it down a bit.

[followbl]

@jamesmosier yes works locally, not in prod - (buried in my long-winded comment above I mentioned it)

[timneutkens]

Thanks for the report! Had @ijjk look into this, here's the PR to fix it: vercel/vercel#4778

[followbl]

@timneutkens least I can do. Thank you and the Next.js team for all your work on an amazing piece of software.