This add-on allow your Google Result become two column (see the screenshot), which let you feel comfortable in wide window. Besides, because of google's layout, this add-on would move you extra content to right side, all you need to do is moving your mouse over it, then you could see all content of it :)
In 2.0.0, this add-on would provide a button (at the right side of link bar), you could switch two-col effect on/off by easily clicking that button.
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ps: this add-on also work on startpage.com after v2.3.0
