`useTransition` stuck in loading state when using `router.refresh()` after calling a server action

[vinassefranche]

Link to the code that reproduces this issue

https://github.com/vinassefranche/use-transition-hanging

To Reproduce

1. build the application as the issue only occurs on the built version: pnpm run build
2. serve the application: pnpm run start
3. go to http://localhost:3000/ in a browser
4. click on the "trigger action" button
5. see the button being stuck in loading... state and the render date not being updated

If the button is not stuck, click on it a few times. If still not, re-start the application and try again. If not, add more <BigBlock /> in the page as it seems like the more blocks we add, the more likely the issue is to occur

Current vs. Expected behavior

The page is not re-rendered and the button is stuck on the loading state while the page should be re-rendered and the button not in loading state.
The issue is not always present though, even though it's there most of the case. It can occur on the first click but can work a few times and then not work. It seems like the more content I add to the page, the more likely the issue is to occur.

Here's a video of the issue:

Screencast.from.2025-11-12.21-18-42.webm

Here are a few things that I found made the issue disappear:

• remove the loading.tsx file
• downgrade next to the version 15.4.7 (works even when specifying --turbopack to the build command)
• keep only one <BigBlock /> in the page
• stop awaiting fakeDataRetrieval()

Provide environment information

Operating System:
  Platform: linux
  Arch: x64
  Version: #29~24.04.1-Ubuntu SMP PREEMPT_DYNAMIC Thu Jun 26 14:16:59 UTC 2
  Available memory (MB): 63932
  Available CPU cores: 22
Binaries:
  Node: 22.20.0
  npm: 10.9.3
  Yarn: 1.22.22
  pnpm: 9.15.5
Relevant Packages:
  next: 16.0.1 // There is a newer version (16.0.2) available, upgrade recommended! 
  eslint-config-next: N/A
  react: 19.2.0
  react-dom: 19.2.0
  typescript: 5.9.3
Next.js Config:
  output: N/A

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

Not sure

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

next start (local)

Additional context

I tested the code with different versions of next and managed to find that the issue came with this commit

[denk0403]

Seems like this might be closely related to #84299 as well.

[vinassefranche]

I found out that removing the loading.tsx file while adding a Suspense around the page content also has the issue. Here's a branch on the reproduction repository that shows it.

[eps1lon]

@vinassefranche I cannot reproduce the described issue in Chrome on the repository you provided.

The issue says 16.0.1 but the repository uses 16.0.2. Is the repository reflecting the original issue? Can you include a video recording of the bad behavior?

[vinassefranche]

@eps1lon The issue exists in both 16.0.1 and 16.0.2 (and in 16.0.3 and 16.0.4 too by the way)

I had the issue on Brave but just tested on Chrome and I still have the issue.
Here's a recording of my last test with the full setup:
https://github.com/user-attachments/assets/c4e0c662-87ec-4766-b04b-db68115bba9a

Is there anything else I can do to help troubleshoot this?

Thanks for having a look anyway!

I also made a colleague that works on a Mac test the issue with the repo and he had it too, FYI.