Turbopack doesn't support global SASS

[dobrakmato]

Using next=15.4.2.

single import in _app.tsx

import "../ui/globals.sass";

leads to rather funny error, where turbopack/next.js complains that I shoudn't be importing the global CSS from _app.js, but move it to _app.js 😄 :

Failed to compile
    Global CSS cannot be imported from files other than your Custom <App>. Due to the Global nature of stylesheets, and to avoid conflicts, Please move all first-party global CSS imports to pages/_app.js. Or convert the import to Component-Level CSS (CSS Modules).
    Read more: https://nextjs.org/docs/messages/css-global
Location: pages/_app.tsx
Import path: ../ui/globals.sass

One idea that comes to my mind is that maybe the error really has "app.js" hardcoded, and completely ignores other extensions (jsx, tsx, ...).

Workaround: Do not use turbopack and the error disappears.