fix(nextjs): Return NextResponse instead of native Response (#6388)

Author: brkalow

.changeset/olive-sides-allow.md

@@ -0,0 +1,5 @@
+---
+'@clerk/nextjs': patch
+---
+
+Fixes an issue where `clerkMiddleware()` would not properly redirect or set cookies in some environments.

packages/nextjs/src/server/clerkMiddleware.ts

@@ -195,7 +195,14 @@ export const clerkMiddleware = ((...args: unknown[]): NextMiddleware | NextMiddl
 
       const locationHeader = requestState.headers.get(constants.Headers.Location);
       if (locationHeader) {
-        return new Response(null, { status: 307, headers: requestState.headers });
+        const res = NextResponse.redirect(locationHeader);
+        requestState.headers.forEach((value, key) => {
+          if (key === constants.Headers.Location) {
+            return;
+          }
+          res.headers.append(key, value);
+        });
+        return res;
       } else if (requestState.status === AuthStatus.Handshake) {
         throw new Error('Clerk: handshake status without redirect');
       }