new URL("d:\file.txt")
  hash: ""
  host: ""
  hostname: ""
  href: "file:///D:/file.txt"
  origin: "file://"
  password: ""
  pathname: "/D:/file.txt"
  port: ""
  protocol: "file:"
  search: ""
  searchParams: URLSearchParams {}
  username: ""

new URL("d:\file.txt")
  hash: ""
  ​host: ""
​  hostname: ""
  ​href: "d:\file.txt"
  ​origin: "null"
​  password: ""
  ​pathname: "\file.txt"
  ​port: ""
​  protocol: "d:"
  ​search: ""
  ​searchParams: URLSearchParams {  }
​  username: ""

node -e "console.log(new URL('d:\file.txt'))"
  hash: ''
  host: ''
  hostname: ''
  href: 'd:\file.txt'
  origin: 'null'
  password: ''
  pathname: '\file.txt'
  port: ''
  protocol: 'd:'
  search: ''
  searchParams: URLSearchParams {}
  username: ''