The Customize Toolbar dialog allows you to modify the appearance of your toolbar items in regards to their icon and text labels. At the bottom of the window is a drop-down menu labeled Show, containing the following options:
- Icons and Text: Displays both labels, icon and text, for each of your toolbar items.
- Icons: Displays only icons for each of your toolbar items.
- Text: Displays only text for each of your toolbar items.
Please note that this selection affects all of your Firefox toolbars, not just the newly created one.