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Google Homepage show/hide header
Add link to show/hide all the header above the tabs on your Google home page.
Here's a screencast to show it in action and a short description of how it does it: http://www.screencast-o-matic.com/watch/cietogf5
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I use a userstyle to do the same thing: http://userstyles.org/style/show/1940 This style uses the :hover css pseudo-class to show the full header when you move your cursor over the collapsed one.