User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:2.0b8pre) Gecko/20101124 Firefox/4.0b8pre Build Identifier: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:2.0b8pre) Gecko/20101124 Firefox/4.0b8pre On Windows, Win7 taskbar tabs preview is enable. However it says hard that this function has the consistency to Firefox Panorama. Also Windows 7's Aero peek taskbar preview is not useful when many tabs opened. But Panorama causes opening many tabs. So I think these functions are conflict for usability. Should it be disable default preference of browser.taskbar.previews.enable, isn't it? Reproducible: Always Steps to Reproduce: 1.Move some tabs to background Panorama group from current Panorama group. 2.Hover mouse cursor on taskbar to display tab thumnail preview. Actual Results: There is showing not only tabs in current Panorama group but also backgronud Panorama group.