I noticed that raising an Emacs frame (latest master) with emacsclient does nothing under current Cinnamon. Emacs gains focus, but the focused window isn't raised.
I can reproduce the problem with xdotool's windowraise command, which similarly did nothing. xdotool windowactivate works though, so I'm guessing the EWMH activate code in xterm.c would similarly do the trick. Emacs used to use EWMH activate on frame raise but stopped in 2007 to work around deadlocks in a version of metacity in use at the time. Can we once again activate Emacs frames on raise?