Gmail “Title Tweaks” displays unread email count in the browser’s title bar.
Gmail displays the unread email count on the active Window/Tab but when the window/tab becomes inactive then it just displays “Gmail – In…” on the window’s title bar. Gmail Labs just released a new feature “Title Tweaks”, with which it displays the count of unread emails in the browser’s title bar. It would come-in really handy when you minimize the browser window and wanted to glance at to see if you have received new emails.
Enable the feature at Gmail Labs by enabling “Title Tweaks”.