Unable to parse config export in source file error in middleware.js example

Verify canary release

[X] I verified that the issue exists in the latest Next.js canary release

Provide environment information

NodeJs v18.17.1 Local Environment

Which example does this report relate to?

with-strict-csp

What browser are you using? (if relevant)

No response

How are you deploying your application? (if relevant)

No response

Describe the Bug

I encountered an issue with the middleware.js example provided in the Next.js documentation. When trying to use the config export with a complex matcher configuration, I received the following error:

Unable to parse config export in source file
The exported configuration object in a source file needs to have a very specific format from which some properties can be statically parsed at compile-time.

export const config = { matcher: [ { source: "/((?!api|_next/static|_next/image|favicon.ico).*)", missing: [ { type: "header", key: "next-router-prefetch" }, { type: "header", key: "purpose", value: "prefetch" }, ], }, ], };

The syntax that works well is this: export const config = { matcher: [ '/((?!api|_next/static|_next/image|favicon.ico).*)', ], };

Expected Behavior

To Reproduce

just run the with-strict-csp example

vercel / next.js