Do you want to try a cool hidden feature of Firefox. Personally I am not sure why this feature is not turned on by default. Maybe some my find it annoying, but I like it. Its gives Firefox a tab preview feature that use to only be in Internet Explorer for Windows 7.
- Launch Firefox
- In the URL field type: ABOUT:CONFIG
- In the Filter field type: browser.taskbar.previews.enable
- Change the value of the preference name to: True
Note: This feature is only available in Windows 7