PSA for people who don't like the new Firefox look

and it's okay if you do, I'll still love you. :-)

If you prefer your browser old-school:
Classic Theme Restorer
https://addons.mozilla.org/en-US/firefox/addon/classicthemerestorer
For reverting (almost) everything

Or for one particular peeve

Tabs on Bottom
https://addons.mozilla.org/en-US/firefox/addon/fdgueux-tabs-on-bottom
If you want your tabs attached to the webpage, not above the other tool bars.

New Add-on Bar
https://addons.mozilla.org/en-US/firefox/addon/new-add-on-bar
If you want your add-on icons back at the bottom of the window, rather than in the address bar.

Classic Bookmarks Button
https://addons.mozilla.org/en-US/firefox/addon/classicbookmarksbutton
If you want the old-style single bookmark menu button