Evo ispravila sam, sada je ovako:
// ==UserScript==
// @name Test
// @namespace Test
// @description Test
// @version 1
// @include *
// @grant none
// @run-at document-start
// ==/UserScript==
function addGlobalStyle(css) {
var head, style;
head = document.getElementsByTagName('head')[0];
if (!head) { return; }
style = document.createElement('style');
style.type = 'text/css';
style.innerHTML = css;
head.appendChild(style);
}
window.onload = function() {
addGlobalStyle("body { display: none; }");
document.body.innerHTML = document.body.innerHTML.replace('International Conference on Sustainable Aggregates Planning in South East Europe','**************************************' );
document.body.style.display = "block";
};
Ali opet ne radi, evo pokušavam na konkretnom sajtu i neće.