PreventPageVisibility

Block websites from knowing if you switched tabs/windows

K instalaci tototo skriptu si budete muset nainstalovat rozšíření jako Tampermonkey, Greasemonkey nebo Violentmonkey.

You will need to install an extension such as Tampermonkey to install this script.

K instalaci tohoto skriptu si budete muset nainstalovat rozšíření jako Tampermonkey nebo Violentmonkey.

K instalaci tohoto skriptu si budete muset nainstalovat rozšíření jako Tampermonkey nebo Userscripts.

You will need to install an extension such as Tampermonkey to install this script.

K instalaci tohoto skriptu si budete muset nainstalovat manažer uživatelských skriptů.

(Už mám manažer uživatelských skriptů, nechte mě ho nainstalovat!)

You will need to install an extension such as Stylus to install this style.

You will need to install an extension such as Stylus to install this style.

You will need to install an extension such as Stylus to install this style.

You will need to install a user style manager extension to install this style.

You will need to install a user style manager extension to install this style.

You will need to install a user style manager extension to install this style.

(Už mám manažer uživatelských stylů, nechte mě ho nainstalovat!)

// ==UserScript==
// @name        PreventPageVisibility 
// @namespace   https://github.com/IceWreck
// @match       *://*/*
// @run-at      document-start
// @grant       none
// @version     1.1
// @author      IceWreck
// @description Block websites from knowing if you switched tabs/windows

// ==/UserScript==

// This userscript blocks the page visibility API and to some extent the old blur/focus APIs.

let events_to_block = [
  "visibilitychange",
  "webkitvisibilitychange",
  "mozvisibilitychange",
  "hasFocus",
  "blur",
  "focus",
  "mouseleave"
]

for (event_name of events_to_block) {
  document.addEventListener(event_name, function (event) {
      event.preventDefault();
      event.stopPropagation();
      event.stopImmediatePropagation();
  }, true);
}

for (event_name of events_to_block) {
  window.addEventListener(event_name, function (event) {
      event.preventDefault();
      event.stopPropagation();
      event.stopImmediatePropagation();
  }, true);
}


document.hasFocus = function () { return true; };
document.onvisibilitychange = null;
Object.defineProperty(document, "visibilityState", { value: "visible" });
Object.defineProperty(document, "hidden", { value: false });
Object.defineProperty(document, "mozHidden", { value: false });
Object.defineProperty(document, "webkitHidden", { value: false });
Object.defineProperty(document, "webkitVisibilityState", { value: "visible" });