Greasemonkey script to disable keyboard hijacking

keyboard hijacks.js

// ==UserScript==
// @name           Disable keyboard hijacking
// @description    Stop websites from highjacking keyboard shortcuts
//
// @run-at         document-start
// @include        *
// @exclude        https://www.youtube.com/*
// @grant          none
// ==/UserScript==

(window.opera ? document.body : document).addEventListener('keydown', function(e) {
  e.cancelBubble = true;
  e.stopImmediatePropagation();
  return false;
}, !window.opera);