nextjs - 💡(How to fix) Fix beforeFiles rewrites with locale: false and has conditions stopped firing in 16.2.0 [1 comments, 2 participants]

Link to the code that reproduces this issue

https://github.com/seth146/ksebe-headless-web (private repo — reproduction details below)

To Reproduce

1. Configure Next.js with Pages Router and domain-based i18n
2. Add a beforeFiles rewrite with locale: false and a has condition matching a query parameter:

async rewrites() {
  return {
    beforeFiles: [
      {
        source: '/:path(.*)',
        has: [
          {
            type: 'query',
            key: 'my-preview-token',
            value: '(?<token>.+)',
          },
        ],
        destination: '/api/my-handler',
        locale: false,
      },
    ],
    afterFiles: [],
    fallback: [],
  }
}

1. Deploy to Vercel
2. Make a request with the query parameter: /?my-preview-token=some-value

Current vs. Expected behavior

Expected: The beforeFiles rewrite should match and internally route the request to /api/my-handler.

Current (16.2.0+): The rewrite does not fire. The request passes through to the page handler as if the rewrite doesn't exist. The rewrite config IS present in the build output (verified).

Provide environment information

• Next.js: 16.2.0 and 16.2.1 (regression)
• Last working version: 16.1.7
• Platform: Vercel (deployed)
• i18n: Pages Router with domain-based routing
• Build: Turbopack (default)

Which area(s) are affected?

• Routing (rewrites)
• Internationalization (i18n)

Verified by bisecting

Impact

This breaks the Makeswift visual editor integration, which relies on a beforeFiles rewrite with locale: false and has conditions to intercept preview token requests. The @makeswift/next-plugin adds this rewrite automatically. Since 16.2.0, the Makeswift editor cannot load page previews.

Additional context

• The rewrite config is verified correct in the resolved Next.js config at build time
• The has condition matches a query parameter (not a header or cookie)
• The locale: false flag is required because the rewrite destination is an API route
• Same config works perfectly on 16.1.7 and earlier