Not sure the attachment uploaded.

Nobody Knows?

Those are empty spaces on either side of the URL can be removed you have right click on the url location and "customize" and you can remove those empty spaces. That location is part of the "Customize" option you will see it if you right click and pick customize. Those other spaces between the file and icons are the separation lines those can't be removed.

WestEnd said

Those are empty spaces on either side of the URL can be removed you have right click on the url location and "customize" and you can remove those empty spaces. That location is part of the "Customize" option you will see it if you right click and pick customize. Those other spaces between the file and icons are the separation lines those can't be removed.

Thank you for responding. I do not mean the space between the various urls tabs. I meant the seemingly blank "row" located below the "File, Edit, View...." menu bar and the row of open tabs below. The row of open tabs should be positioned closer to the Menu bar above it. I already have the density set to compact in the customize screen but there remains (IMHO) unnecessary wasted space above the row of open tabs.

https://www.howtogeek.com/333110/how-to-customize-firefox-quantum-and-remove-the-white-space-around-the-title-bar/

it can be taken out. Depends on the resolution as to what it looks like this 32" LG TV 1920x1080 There is not enough gap to remove, on a 800x ya there was some.... so depends on your resolution, and plans if move between screens or laptop into a.....

might need userChromeCss to do something. Not sure.