Cannot use :export psedo-class in scss module

[szaleq]

Link to the code that reproduces this issue

https://github.com/szaleq/next-js-15-sass-issue-repro

To Reproduce

1. Create new Next.js app yarn create next-app@latest
2. Install sass yarn add sass
3. Add example sass code exporting variables from documentation

Current vs. Expected behavior

Expected behavior: Sass variables defined using :export {} are correctly imported in JS using the following code:

import vars from './vars.module.scss';

Current behavior: fails with the following error:

'export' is not recognized as a valid pseudo-class. Did you mean '::export' (pseudo-element) or is this a typo? at [project]/src/app/vars.module.scss.module.css:0:2

Everything works as expected with Next.js 13 and 14 (just following the steps described above but adding version to create-next-app, like yarn create next-app@^13) but fails with next@15.

Provide environment information

Operating System:
  Platform: win32
  Arch: x64
  Version: Windows 10 Pro
  Available memory (MB): 65306
  Available CPU cores: 32
Binaries:
  Node: 18.18.2
  npm: 10.2.3
  Yarn: 4.5.3
  pnpm: 9.4.0
Relevant Packages:
  next: 15.0.3
  eslint-config-next: 15.0.3
  react: 19.0.0-rc-66855b96-20241106
  react-dom: 19.0.0-rc-66855b96-20241106
  typescript: 5.7.2
Next.js Config:
  output: N/A

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

Not sure, Module Resolution

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

next dev (local)

Additional context

No response

[victorvianaom]

Same for me, with 2 different libs:

excalidraw

odometer

[victorvianaom]

It's not a bug, turbopack does not support :export ICSS rule.

https://nextjs.org/docs/architecture/turbopack#unsupported-features

---

* is also considered by them invalid css

[jaandrews]

Ran into this issue myself after upgrading to nextjs 16.0.1, which defaults to using turbopack. I understand the reason it no longer works, but is there a new recommended approach to pull scss variables into the javascript, or is it just no longer possible? Current sass documentation only shows the method that no longer works.

[sKopheK]

wanted to add the link myself. it's contradictory what documentation says and what next build process actually does