User-Agent: Mozilla/5.0 (Windows NT 6.1; rv:2.0b11) Gecko/20100101 Firefox/4.0b11 Build Identifier: Mozilla/5.0 (Windows NT 6.1; rv:2.0b11) Gecko/20100101 Firefox/4.0b11 I have activated the option to show a preview of each tab in windows' application bar. Having more then one group in panorama and previewing a window from another group (with respect to the one that is currently displayed) the window is added to the current group rather then switching to the other group. Reproducible: Always Steps to Reproduce: 1.Make sure that in the Options page (under the Tab tab) “Show tab preview in the Windows taskbar” is checked. 2.Create 2 groups in panorama with some tabs in each of it. 3.Go over firefox's icon in windows' taskbar and preview it (WITHOUT CLICKING). 4.Go back in firefox. Actual Results: The previewed tab is added in the window (but not in the group) Expected Results: No tab is added in the window Using Stylish 1.1 and Simple&Clean grey edition theme