What else do you have on that toolbar? You may be able to move items to other toolbars by using Customize. Right-click on a toolbar and select Customize Toolbar. Once that is open, you can drag some items to other positions including the Overflow Menu. You may have to show the title bar or menu bar first.

Is that about making the location bar wider or about making it higher ?

Note that you can also look at the Density setting at the bottom of the Customize page.

• https://support.mozilla.org/en-US/kb/customize-firefox-controls-buttons-and-toolbars