Redirect from Server Action executes hard navigation

[swa-legste]

Link to the code that reproduces this issue

https://github.com/swa-legste/next-reproduction

To Reproduce

1. Start the application in development (next dev)
2. Open applicaiton over http://localhost:3000
3. click on any "Add To Cart" button
4. wait until action completion

Current vs. Expected behavior

expected
After "Add to Cart" the page is redirected to the /basket url. Given that /basket is parallel route (drawing an overlay) with a null default on main slot I'm expecting to see the basket overlay while keeping the main slot unchanged as follow:

note that this can be seen by navigating to the basket from the header link.

actual
Instead the main slot is empty:

Verify canary release

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

Provide environment information

Operating System:
  Platform: linux
  Arch: x64
  Version: #1 SMP PREEMPT_DYNAMIC Mon Jan  1 18:15:01 PST 2024
Binaries:
  Node: 20.11.0
  npm: 10.2.4
  Yarn: 1.22.21
  pnpm: 8.14.0
Relevant Packages:
  next: 14.0.5-canary.65
  eslint-config-next: 14.0.4
  react: 18.2.0
  react-dom: 18.2.0
  typescript: 5.3.3
Next.js Config:
  output: N/A

Which area(s) are affected? (Select all that apply)

App Router
Routing (next/router, next/navigation, next/link)

Which stage(s) are affected? (Select all that apply)

next dev (local), next start (local)

Additional context

The server action executes a redirect which is taken as a hard redirect from the browser? This might be related to #54173 and partially fixed (at least redirects executes) by #59585.

Root cause being the redirect('/basket') in the server action.

Whil this might be the exepcetd behavior it makes using parallel routes for modal cumbersome.

also tested against latest canary 14.1.1-canary.1

[swa-legste]

this is fixed by #63607