You’ve gotten good responses already, but I just live and let live with Gnome’s Mutter & KDE’s Kwin. It’s worth mentioning that they’re both highly polished offerings. But I would also understand why one wouldn’t want to use either.

I use Firefox as I actually like it more, except for the lack of Chrome-style tab groups (in development). But it does seem like it’s mismanaged and I wonder what that means for it in upcoming years.