Middle Click To Go Back door keremonal

Click middle mouse button on an empty space on the page to go back.
And optionally, you can set middle-click to close the tab if no page to go back.

While keeping the old behaviors:
Click middle mouse button on a link to open it on a new tab.
Click middle mouse button on a specific tab to close that tab.
In Linux, click middle mouse button on a text input to paste selected text.

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For Google Chrome: http://goo.gl/cnR67