I'll add my personal peeve: Ctrl-Z in a terminal, as we all know, works (via SIGSTOP and process group handling) to return control to the shell that launched th

I'll add my personal peeve: Ctrl-Z in a terminal, as we all know, works (via SIGSTOP and process group handling) to return control to the shell that launched the process. And emacs supports similar behavior (even though its tty is in raw mode) for symmetry, and that makes sense. But at some point the emacs folks decided that in a X11 window, Ctrl-Z should be bound to the same kind of idea: it minimizes the window! So you're happily typing along and hit C-x <something> and... your window just disappears because you missed and hit the adjacent key. Terrible default, have had it disabled for decades.