After upgrading from mate 1.10.x to mate 1.12.x packages the suspend button is missing in the menu and not working with keyboard shortcuts. However, I can suspend without problems from commandline with pm-suspend. I assume this bug is related to mate-polkit-1.12.0-r2, mate-session-manager-1.12.2-r1 and/or mate-power-manager-1.12.1-r2. I have following use-flags: =mate-session-manager-1.12.2-r1 upower -systemd =mate-power-manager-1.12.1-r2 -pm-utils On my system I have sys-power/pm-utils ant not sys-power/upower-pm-utils.
A lot has changed since 1.10/1.12. If you can still reproduce this problem, please reopen this bug with additional information.