https://addons.mozilla.org/en-US/firefox/addon/the-addon-bar/
About this Add-on
Adds back the addon bar for Firefox with the Australis theme (Firefox 29 and
up).
It aims to be a lightweight, yet fully functional replacement for the old
Addon Bar.
Great for power users who have many addons installed, and especially for long
toolbar items.
This also restores the status-bar area, so it works with extensions such as
Status-bar Scientific Calculator, Version in Add-on bar, and Forecastfox
Weather. Plus, it adds a new feature that lets you move the status-bar around!