If you are referring to the Firefox toolbars, you may want to try using Firefox in fullscreen mode. This should automatically hide the toolbars until your mouse touches the edge of your computer screen.

To start Firefox fullscreen mode, you can to one of the following:

1. Press the F11 key on your keyboard
2. Press the Fullscreen button on your toolbar/menu (may need to customize toolbars)
3. Select Fullscreen from the View section of the menu bar

To exit Firefox fullscreen mode, you can repeat one of the options above.

Please note that the fullscreen button on your toolbar/menu may not be visible by default. To add this button to your browser, please refer to this Mozilla support article for steps on how to customize your toolbar and menu:

• Customize Firefox controls, buttons and toolbars

I hope that this is the information that you were looking for. If not, please let us know.

Used the F11 key and not only did it clear the upper Firefox tool bars but also the bottom Windows 7 tool bar. Excellent solution.