FxButton

Change menu and give an opportunity to move the Firefox button.

Warning! This extension doesn't work since Firefox 29. And I don't have plans to update them. I'm sorry.

Tips and tricks

I. How to change position of the Firefox button?

1. Install extension.
2. Right click an empty space of a toolbar, select "Customize".
3. Drag the button to your favorite place.
4. Click "Done" in the Customize Toolbar window.

II. You can use middle click to open new tab.

Screenshot