FlexBar is a Firefox add-on, can easily configure the visibility of all menu bars, sidebars and information bars. For every element you can adjust separately whether it is shown never, always or automatically. The automatic display mechanism can be globally deactivated.

To configure the display state of a bar, open the FlexBar menu by clicking on the small arrow on the right of the FlexBar icon. Now click on the name of the element which state you want to change. The small icon in front of the name then toggles beween the following display states:
1. The element is always shown
2. The element is never shown
3. The element is shown automatically

The Navigation Toolbar and the Tab Bar cannot be configured to be always hidden. An invisible Navigation Toolbar would make it impossible to handle the Add-on and with an invisible Tab Bar the usage of Firefox would be nearly impossible. Additionally, under Mac OS X the Menu Bar cannot be configured since it is always shown by the system regardless.

Requirements:
* Firefox

The license of this software is Freeware, you can free download and free use this browser plug-ins software.