opened video files will fill your browser window
// ==UserScript==
// @name fit video to window
// @namespace hvideolooper
// @author h
// @description opened video files will fill your browser window
// @include *.webm
// @include *.mp4
// @run-at document-start
// @version 0
// @grant none
// ==/UserScript==
document.getElementsByTagName("video")[0].setAttribute("width", "100%", "height", "100%");