HTMLDocument
HTMLDocument is an abstract interface of the DOM which provides access to special properties and methods not present by default on a regular (XML) document.
Its methods and properties are included in the document page and listed separately in their own section in the above linked DOM page.
Specification
License
© 2016 Mozilla Contributors
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-us/docs/web/api/htmldocument