Link to the code that reproduces this issue

https://github.com/JClackett/next-reproduction-app

To Reproduce

So, I literally have no idea how to reproduce this consistently yet, but will keep trying.

I'm getting this error semi-often in production only and only sometimes for certain users, most of the time it's working.

Looking at the stack trace (which is limited), it's due to some call to a <cache>.parallelRoutes.get. Searching the next code base with https://github.com/search?q=repo%3Avercel%2Fnext.js%20parallelRoutes.get&type=code
shows all the times this method is called.

It seems that one of the cache objects is null for me? How would I go about creating a repro for that. Or does anyone have any idea why this cache object would be null in the first place. The page this is erroring on is nothing special, it's just a async server component that fetches data and renders few components, one being a client component, so I dont see (yet) how this is something strange with my setup. Only thing of note is that im using react suspense to handle the fallback because the loading.tsx pages dont work as id like (they dont trigger on search param changes).

Current vs. Expected behavior

Doesn't crash

Provide environment information

Like I said, only in production and on vercel.
Operating System:
  Platform: darwin
  Arch: arm64
  Version: Darwin Kernel Version 23.1.0: Mon Oct  9 21:27:24 PDT 2023; root:xnu-10002.41.9~6/RELEASE_ARM64_T6000
  Available memory (MB): 32768
  Available CPU cores: 8
Binaries:
  Node: 18.18.2
  npm: 9.8.1
  Yarn: 1.22.19
  pnpm: 8.15.7
Relevant Packages:
  next: 14.2.5 // Latest available version is detected (14.2.5).
  eslint-config-next: N/A
  react: 18.3.1
  react-dom: 18.3.1
  typescript: 5.5.3
Next.js Config:
  output: N/A

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

Navigation, Runtime

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

Vercel (Deployed)

Additional context

Only in production on vercel