User Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:54.0) Gecko/20100101 Firefox/54.0 Build ID: 20170628075643 Steps to reproduce: Firefox automatically moved my address bar back to the center left if the toolbar Go into customize firefox to fix it. Actual results: Address bar is immovable and is greyed out in the customize screen. it blocks view of a character in my custom theme Expected results: The address bar should not have moved back on its own and I should be able to move it back to where I had it

This is fixed in Firefox 57. In the meantime, on Firefox 54/55/56, you can work around the issue by moving other items around the location bar instead of moving the location bar around the other items.