This issue appears only on Windows, likely due to the way the plugin //example.com/... as a local file path instead of an external resource. The plugin then tries to resolve and read the URL as if it were a file, causing Rollup to freeze indefinitely.

🛠 Steps to Reproduce:
Add the following to a CSS file:

@font-face {
    font-family: 'Open Sans';
    src: url("//example.com/fonts/open-sans.woff") format("woff");
}

Use rollup-plugin-styles in rollup.config.js:

import styles from 'rollup-plugin-styles'; // 4.0.0

export default {
  input: 'index.js',
  output: { file: 'dist/bundle.js', format: 'es' },
  plugins: [styles()]
};

package.json

...
"scripts": {
  "dev": "rollup -c"
}

✅ Expected Behavior:
The plugin should not attempt to resolve //example.com/... as a local file.
It should leave the URL unchanged in CSS.

As far as I debugged this, it happens here: