Rated 4 out of 5 stars

My only gripe about it is that unlike Outlook, you can't simply press the minimize button to minimize to the tray. In fact when it comes to email clients I think minimizing to the taskbar is quite useless, they should all be designed to minimize to the tray by default, like Outlook. It's quite a simple concept, I don't know why Mozilla hasn't just put a simple button in their Options menu for this. But this is better than nothing, thanks.