steam-store.user.js

// ==UserScript==
// @name Steam Web Tools Steamstore Page MOD
// @include https://store.steampowered.com/*
// @include  http://store.steampowered.com/*
// @exclude https://store.steampowered.com/checkout/sendgift/*
// @exclude  http://store.steampowered.com/checkout/sendgift/*
// ==/UserScript==

window.addEventListener("DOMContentLoaded",function() {

    // for age check
    if(window.location.pathname.indexOf('/agecheck')==0){
        document.cookie='birthtime=-1704124799; expires=21-Dec-2112 00:00:00 GMT; path=/';
        window.location.reload();
    }

    /*// to top btn
    var tmp='<style>#footer{z-index:2;position: relative;}#totop{padding:10px;background:#000;position:fixed;left:0;width:90px;height:100%;z-index:2;cursor:pointer;opacity:0}#totop:hover{opacity:.5}</style><div id="totop" onclick="document.body.scrollTo()">Наверх</div>'
    document.querySelector('body').insertAdjacentHTML('afterBegin', tmp);
    */

    // cc switcher
    var global_action_menu = document.getElementById('global_action_menu');
    if(global_action_menu) {
        var curCC = false;
        if(curCC = document.cookie.match(/fakeCC=(\w+?);/i)){
            curCC = curCC[1];
        }
        var changeCCmenuHTML = '\
        <style>#cc_menu_btn{min-width:59px;z-index:999;position:fixed;right:0;top:0;background-color:#000;opacity:0.5;}#cc_menu_btn:hover{opacity:1}#cc_list .popup_menu_item{white-space:nowrap}</style>\
        <span class="pulldown" id="cc_menu_btn" onclick="ShowMenu(this, \'cc_menu\', \'left\', \'bottom\', true);">CC'+((curCC)?': <img src="http://icons.iconarchive.com/icons/famfamfam/flag/16/'+curCC.toLowerCase()+'-icon.png" /> '+curCC:'')+' </span>\
<div class="popup_block" id="cc_menu" style="display:none;">\
<div class="popup_body popup_menu shadow_content" id="cc_list"></div></div>\
    <div class="popup_block" id="cc_list_edit" style="display:none;">\
    <div class="popup_body popup_menu shadow_content">\
    <input id="ccListEdit" type="text" value="'+_cc.curList+'"/><br/><a title="OK" href="#" id="cc_okbtn">[OK]</a> <a title="Default" href="#" id="cc_defbtn">[D]</a>\
    </div></div>';

        global_action_menu.insertAdjacentHTML('afterBegin', changeCCmenuHTML);

        _cc.updHTMLccList();

        document.getElementById('cc_defbtn').onclick = _cc.setDefCcList;
        document.getElementById('cc_okbtn' ).onclick = _cc.saveNewList;
    }

},false);

window.setDefCcList = function(){alert(1)};

_cc = {
    defList : 'ru us ua fr gb au',
    updHTMLccList : function(){
        var s='';
        var ccListA = _cc.curList.split(' ');
        for(var i=0; i < ccListA.length; i++){
            s += '<a class="popup_menu_item" href="'+_cc.url+ccListA[i]+'"><img src="http://icons.iconarchive.com/icons/famfamfam/flag/16/'+ccListA[i]+'-icon.png" style="width:16px"/> '+ccListA[i].toUpperCase()+'</a>';
        }
        s += '<a class="popup_menu_item" title="Редактировать" href="#" onclick="ShowMenu(this, \'cc_list_edit\', \'right\', \'bottom\', true);return false"><img src="http://cdn.steamcommunity.com/public/images/skin_1/iconEdit.gif" style="width:16px"/></a>';
        document.getElementById('cc_list').innerHTML=s;
    },
    saveNewList : function(){
        _cc.curList=document.getElementById('ccListEdit').value;
        window.localStorage.ccList=_cc.curList;
        _cc.updHTMLccList();
        return false;
    },
    setDefCcList : function(){
        document.getElementById('ccListEdit').value = _cc.defList;
        return false;
    }
};

_cc.curList = window.localStorage.ccList || _cc.defList;

_cc.url = String(window.location);
if (_cc.url.indexOf('?')==-1) {
    _cc.url += '?';
} else {
    _cc.url = _cc.url.replace(/\?.+/, '?');
}
_cc.url += 'cc=';

window._cc=_cc;