how to specify, in nodejs file: URL, a absolute path under windows

I use node.js URL class to parse different user URLs, no problem with usual protocols and no problem with file: urls under linux.

But I have found a problem with file: under windows when the user tries to specify an absolute path like file://C:\temp\test.jpg

> u = new URL('file://C:\\temp\\test.jpg');
URL {
  href: 'file:///C:/temp/test.jpg',
  origin: 'null',
  protocol: 'file:',
  username: '',
  password: '',
  host: '',
  hostname: '',
  port: '',
  pathname: '/C:/temp/test.jpg',
  search: '',
  searchParams: URLSearchParams {},
  hash: ''
}

you can see the u.pathname is '/C:/temp/test.jpg', note the leading /, making the pathname useless.

what is the correct way to specify in an URL in nodejs for an absolute path to a windows file?