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I know I can rearrange the applications in my taskbar in Windows 7, but there doesn't seem to be any way to rearrange the previews for each window. For example, I have Firefox open and the Downloads window open, and for some strange reason the Downloads window is now the left-most window, while the Firefox browser window is number 2. I'd like to rearrange those two so the main browser window is first, but I can't drag or drop them. Is there a power tool to enable this?