gmailUnread user script

gistfile1.js

// ==UserScript==
// @name           gmailUnread
// @namespace      http://webtech-walker.com/
// @author         hokaccha (Kazuhito Hokamura)
// @include        http://mail.google.com/*
// @description add shortcut key is:unread search query
// ==/UserScript==

(function(){
    document.addEventListener('keypress', function(e){
        var s = document.getElementById(":ra");
        if(!s) return;

        //default key code is <C-/>
        var key     = 47;
        var key_win = 63;
        var is_win  = (navigator.userAgent.indexOf("Win") != -1);

        if((e.charCode == key && e.ctrlKey) || (is_win && e.shiftKey && e.ctrlKey && e.charCode == key_win)) {
            if(e.shiftKey) {
                if(s.value.indexOf('is:unread') == -1) {
                    s.value += " is:unread";
                }
            } else {
                s.value = "is:unread"
            }
            s.focus();
        }
    }, true);
})();