gistfile1.txt

// ==UserScript==
// @name         Remove blur event
// @version      0.1
// @description  Remove all blur events
// @author       unknown
// @match        **
// @grant        none
// ==/UserScript==

window.addEventListener("blur", function(event) {
    event.stopImmediatePropagation();
}, true);

window.addEventListener("visibilitychange", function(event) {
    event.stopImmediatePropagation();
}, true);