Nay to 50 shades of gray Rated 5 out of 5 stars
So, what's wrong with a little colour in our lives? I've kept the theme alive after updating to v17. (Sometimes "incompatibility" has everything to do with a best-before date, and nothing to do with getting along with new code.)
I understand the author's disappointment with Mozilla's plan to take away the users' ability to configure the GUI the way we want to use the browser.
On the other hand, why not write an extension that moves the tabs back down (when they're forced up)? That would go along nicely with with this small, colourful improvement to FF's drab gray buttons.