Next 13: setting headers in middleware causes full page reload between navigations

[colinclerk]

Verify canary release

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

Provide environment information

    Operating System:
      Platform: darwin
      Arch: x64
      Version: Darwin Kernel Version 21.6.0: Mon Aug 22 20:17:10 PDT 2022; root:xnu-8020.140.49~2/RELEASE_X86_64
    Binaries:
      Node: 16.13.1
      npm: 8.19.1
      Yarn: 1.22.17
      pnpm: 7.12.0
    Relevant packages:
      next: 13.0.0
      eslint-config-next: 13.0.0
      react: 18.2.0
      react-dom: 18.2.0

What browser are you using? (if relevant)

Chrome

How are you deploying your application? (if relevant)

Version 105.0.5195.125 (Official Build) (x86_64)

Describe the Bug

#41380 introduced a way to override headers from middleware.

Using this functionality causes next/link to trigger full-page reload between navigations.

This is only an issue for next dev. There is no bug when it's deployed on Vercel.

Expected Behavior

There should not be a full-page reload when next/link is used.

Link to reproduction

https://github.com/colinclerk/appdir-middleware-bug

To Reproduce

Clone the repo and start the dev server, then click the links between "Index" and "Page 2" - you should see full-page reloads

If helpful, here's the deployed version that doesn't exhibit the issue: https://appdir-middleware-bug.vercel.app/

[mihirsam]

Same happening to me. Following.