What version of Tailwind CSS are you using?

@tailwindcss/postcss v4.0.10+

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

Next.js 15.2.2

What version of Node.js are you using?

v22.14.0

What browser are you using?

N/A

What operating system are you using?

macOS

Reproduction URL

https://github.com/mhornbacher/tailwind-repro

Details
Since version 4.0.10, /**/ style comments in .ts files containing [url] syntax generate the following build error:

HookWebpackError: /Users/menachem/dev/bugs/tailwind-repro/static/css/299a46ed717ed6dc.css:46:4146: Unclosed block

For instance, adding a file like this anywhere in the source code triggers a crash that is challenging to debug:

// junk.ts
/* 
  add a url here [https://github.com/arasatasaygin/is.js]
*/
export function junk() {
  return 1 + 1;
}

To identify this issue, it is recommended to utilize the @tailwindcss/cli to generate an output and subsequently search it for the URL.

The commit that appears most relevant to this issue is: b3c2556