I know that this is likely going to be ignored, but I wanted to at least say something on the topic. Aesthetically, I find the look of the tabs being above the search bar to be quite unappealing, and I find it less efficient for quick bookmarking of a tab.
Though I don't understand why the people managing the design keep thinking that this is a good idea, simply put I am getting tired of constantly having to ask someone else to modify firefox for me to make it more usable. This set up feels clunky, looks awkward, and its getting less worth the hassle. Does anyone here know an easy work around to correct the locations, and if not, any recommendations for a decent browser replacement that seems to actually care about user customization preferences?
The tabs were moved to the top in Firefox 4, and the built-in preference to switch was removed in Firefox 29, so it seems unlikely to be changed at this point. userChrome.css has been the only option for over 5 years.
As part of a gradual process to convert the UI to standard HTML and CSS, Firefox 113 deleted a group of proprietary CSS properties whose names start with -moz-box, including -moz-box-ordinal-number, which was often used in CSS rules as a hack to change the vertical sequence of elements. There are now standard CSS properties you need to use instead.
You can get links and code suggestions in the following Mozilla Support thread, or on the FirefoxCSS subreddit: