[v4] weird webpack warning

[aymanoid]

What version of Tailwind CSS are you using?

@tailwindcss/postcss@4.0.0-beta.2
tailwindcss@4.0.0-beta.2

What build tool (or framework if it abstracts the build tool) are you using?

https://tailwindcss.com/docs/v4-beta#upgrading-from-v3
Next.js 15.0.3

What version of Node.js are you using?

v22.11.0

What operating system are you using?

Windows 11

Reproduction URL

Just a fresh project initiated with pnpx create-next-app@latest, then pnpx @tailwindcss/upgrade@next was used to upgrade to v4

Describe your issue

I keep getting this warning that seems to be related to webpack whenever I run dev or build command. I'm guessing it's something related to Windows' weird pathing, but not sure. The application seems to work fine though.

[philipp-spiess]

This is going to be fixed in the next release (hopefully later this week). Thanks for the report! #15321