URLPattern.username
  The username property of the URLPattern interface is a
  USVString containing the pattern used to match the username part
  of a URL. This value may differ from the input to the constructor due to
  normalization.
Note: This feature is available in Web Workers
Value
A USVString.
Examples
  The below example creates a URLPattern object with admin for
  the username part. This pattern matches only if the username part of the URL
  is admin.
const pattern = new URLPattern({ username: 'admin' });
console.log(pattern.username); // 'admin'
Specifications
| Specification | 
|---|
| URLPattern API # dom-urlpattern-username | 
Browser compatibility
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