The title is wrong. The patent is about how you place the tabs which are opened from already open one and a specific way of closing them. It definitely doesn't patent opening and closing in general. It's more about UI placement and the UX. From the patent itself: "Some browsers provide a tabbed interface. The FIREFOX 2 browser, available at http://www.mozilla.com/, is an example of a browser with a tabbed interface."

Edit: title was wrong (was about google patenting opening/closing tabs), now updated