Link does not automatically prefetch pages for routes with "has" rewrites

What version of Next.js are you using?

12.0.4

What version of Node.js are you using?

14x

What browser are you using?

Chrome

What operating system are you using?

macOS

How are you deploying your application?

Vercel

Describe the Bug

A visible Link will automatically prefetch page json for static pages (along with the chunk) when visible. However, if a rewrite is used to add something like a country code to the route, then the Link will no longer prefetch.

Expected Behavior

Links can prefetch routes with or without a rewrite.

To Reproduce

I’ve created a minimal case here: https://github.com/ericmatthys/nextjs-prefetch-with-rewrite It is deployed here: https://nextjs-prefetch-with-rewrite.vercel.app/

If you look at network requests as you browse through the two different paths, you’ll see the “Without Rewrite” path is able to prefetch and navigate through the path quicker. The “With Rewrite” path does not prefetch.

[ijjk]

This appears to be due to the rewrite using has when on Vercel but not locally so might be a potential duplicate of https://github.com/vercel/next.js/issues/24798

[ericmatthys]

It’s best to use middleware for this sort of rewrite now, which avoids the issue.