User Agent: Mozilla/5.0 (Windows NT 10.0; rv:45.0) Gecko/20100101 Firefox/45.0 Build ID: 20160315153207 Steps to reproduce: 1. Initiate a file download 2. Open Library window listing downloads 3. Close main browser window Actual results: Only main browser window's taskbar button displays the overall download progress. Expected results: When file(s) are being downloaded, the main browser window is closed and the Library window is open but minimized or hidden behind other apps, there is no way to see the completion status at a glance just by looking at the Library window's taskbar button. Thus it would be nice if the Library window's taskbar button could also display the overall download progress.