high90%
Duplicate Location and x-nextjs-stale-time headers in Next.js 15.4.1+ when using redirect/permanentRedirect with force-static
Next.js 15.4.1 introduced a regression where redirects combined with dynamic 'force-static' cause duplicate Location and x-nextjs-stale-time response headers. This can lead to malformed redirect URLs (e.g., '/redirect,/redirect') depending on how clients process the duplicate header.