Userscript for using FastMail in Fluid.app with proper dock badges and (!) Message Center notifications with preview

fastmail_userscript.js

/* Options */
// set dock badge refresh interval here
var refreshInterval = 10*1000; // 10 seconds
// on some systems or networks the site takes a long time to load. specify this time here
var firstTimeout = 3*1000; // 3 seconds work fine for me


var count = 0;
window.fluid.dockBadge = '';

setTimeout(function () {
    setDockBadge(true);
}, firstTimeout);

document.onclick = function () {
    setTimeout(function() {
        setDockBadge(true);
    }, 500);
};

function showNotification() {
    var unreadElms = document.querySelectorAll('.is-unread');
    var unread = [].slice.call(unreadElms);
    unread = unread.map(function(item) {
        return item.id && parseInt(item.id.substr(1));
    });
    var maxId = Math.max.apply(Math, unread);
    var from = document.querySelector('#v' + maxId + ' .v-MailboxItem-name span').innerText;
    var subject = document.querySelector('#v' + maxId + ' .v-MailboxItem-subject').title;
    var body = document.querySelector('#v' + maxId + ' .v-MailboxItem-preview').innerText;
    var n = new Notification('New Mail: ' + from, { body: subject + '\n' + body });
    n.onclick = function () {
        this.close();
    };
}


function setDockBadge(supressNotification) {
    var elm = document.querySelector('.v-FolderSource-badge');
    var newCount = parseInt(elm && elm.innerText);

    if (newCount > count) {
        if (!supressNotification) showNotification();
    }

    count = newCount;

    if (newCount > 0) {
        window.fluid.dockBadge = '' + newCount;
    } else {
        window.fluid.dockBadge = '';
        count = 0;
    }
    setTimeout(setDockBadge, refreshInterval);
}