The address bar in Firefox will automatically shrink to fit your items that you want to put there, so there's no need to manually edit the width of the bar. However, Firefox sometimes automatically puts new icons into the overflow menu. To remove items from the overflow menu and put that on the toolbar instead, you can press the menu button in Firefox and select '''Customize...''' from that menu. Then you can drag and drop any items from the overflow menu directly onto the toolbar. See [[Customize Firefox controls, buttons and toolbars]] for more information. Hope this helps.