MVMNext .hu save passwords wiht Firefox with greasemonkey

/*
I could not get the Firefox to remember my credentials on this freakin website, so I created this 
greasemonkeyscript to bypass that.

Use only on computers where you have safety protections before the browser access...

*/

// ==UserScript==
// @name     MVMNext autologin
// @version  1
// @grant    none
// @include https://www.mvmnext.hu/foldgaz/*
// ==/UserScript==


window.addEventListener('load', function() {
    document.getElementById('loginbox_username').value = "meszaros";
    document.getElementById('loginbox_password').value = "alegokosabb";
  
    document.getElementById('smallloginbox_username').value = "meszaros";
    document.getElementById('smallloginbox_password').value = "alegokosabb";
}, false);