[turbopack] super class not able to set properties on derived class

Link to the code that reproduces this issue

https://github.com/johansunden/my-app

To Reproduce

I am re-opening https://github.com/vercel/next.js/issues/77467

I am also encountering this issue and the original issue was closed without resolution.

The bottom line is, dev and dev --turbo behave differently and that shouldn't be the case.

The usage of "useDefineForClassFields": false does not resolve this issue either.

Current vs. Expected behavior

Derived classes should have defined properties when defined in the super class constructor.

Provide environment information

Operating System:
  Platform: darwin
  Arch: arm64
  Version: Darwin Kernel Version 24.5.0: Tue Apr 22 19:52:00 PDT 2025; root:xnu-11417.121.6~2/RELEASE_ARM64_T6031
  Available memory (MB): 36864
  Available CPU cores: 14
Binaries:
  Node: 22.16.0
  npm: 10.9.2
  Yarn: 1.22.22
  pnpm: N/A
Relevant Packages:
  next: 15.3.3 // There is a newer version (15.3.4) available, upgrade recommended! 
  eslint-config-next: 15.2.3
  react: 19.1.0
  react-dom: 19.1.0
  typescript: 5.8.3
Next.js Config:
  output: N/A
 ⚠ There is a newer version (15.3.4) available, upgrade recommended! 
   Please try the latest canary version (`npm install next@canary`) to confirm the issue still exists before creating a new issue.
   Read more - https://nextjs.org/docs/messages/opening-an-issue

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

Turbopack

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

next dev (local)

Additional context

No response

Start with the linked reproduction at github.com/johansunden/my-app and compare dev with dev --turbo using the reported class inheritance case. Confirm whether the superclass constructor's properties are missing from the derived class, then trace the relevant Turbopack path; done means both modes define those properties consistently.