☰

Let Me Out | TM Edition

Prevents actions (like alerts) when navigating away from a page.

  1. // ==UserScript==
  2. // @name         Let Me Out | TM Edition
  3. // @namespace    tedbigham.blogspot.com
  4. // @version      1.3
  5. // @description  Prevents actions (like alerts) when navigating away from a page.
  6. // @author       Ted Bigham
  7. // @license MIT
  8. // @match        *://*/*
  9. // @icon         https://lh3.googleusercontent.com/UQFgp7s3-HgSxCENa2xNzGQAJhbA6r4VkY1iLAuZrtTBkEQ3cidC5CrkzpyjwYyPK9sXTAECWz1ab_ZJJyLnc96YoKQ=s60
  10. // @grant        none
  11. // ==/UserScript==
  12.  
  13. (function() {
  14.     'use strict';
  15.  
  16.     // Before injection
  17.     var beforeScript = document.createElement('script');
  18.     beforeScript.textContent = `
  19.         Window.prototype.addEventListener2 = Window.prototype.addEventListener;
  20.         Window.prototype.addEventListener = function(type, listener, useCapture) {
  21.             if (type != "beforeunload") {
  22.                 addEventListener2(type, listener, useCapture);
  23.             }
  24.         }
  25.     `;
  26.     (document.head||document.documentElement).insertBefore(beforeScript, (document.head||document.documentElement).firstChild);
  27.     beforeScript.onload = function() {
  28.         this.parentNode.removeChild(this);
  29.     };
  30.  
  31.     // After injection
  32.     var afterScript = document.createElement('script');
  33.     afterScript.textContent = `
  34.         function letmeout() {
  35.             var all = document.getElementsByTagName("*");
  36.             for (var i=0, max=all.length; i < max; i++) {
  37.                 if(all[i].getAttribute("onbeforeunload")) {
  38.                     all[i].setAttribute("onbeforeunload", null);
  39.                 }
  40.             }
  41.             window.onbeforeunload = null;
  42.         }
  43.         letmeout();
  44.         setInterval(letmeout, 500);
  45.     `;
  46.     (document.head||document.documentElement).appendChild(afterScript);
  47.     afterScript.onload = function() {
  48.         this.parentNode.removeChild(this);
  49.     };
  50.  
  51. })();