(Modified 2014 Feb 27)
Upgrading to Xubuntu 13.10 Bibus's compatibility to LibreOffice 4, so I switched to Linux Lite, with is based on Ubuntu 13.04 LTS. I lost some improvements that came is 13.10, but I was happily using Linux before 13.10. Among the functions that don't work in Linux Lite is suspend. I can suspend using xfce4-session-logout, which opens a window with allowed session actions -- i.e., log out, suspend, shut down, etc. -- but no dedicated button on the taskbar would suspend. The suspend option is greyed out in the "Actions button" menu.
I found a solution at AskUbuntu, which was to run
sudo visudoand append the following line:
nonprivilegeduser ALL=NOPASSWD:/usr/sbin/pm-suspend-hybridI then added a launcher to the taskbar that runs 'sudo pm-suspend-hybrid'.
While upgrading to 12.04, my hibernate button disappeared. Apparently, Canonical decided that hibernate didn't work on all hardware, and so they disabled the option everywhere, even for upgrades where it was working before.
To check whether the option to hibernate disappeared for this reason, type:
xfce4-power-manager --dump
If there is a line that says Authorized to hibernate: False, then this is the problem.
The solution (found on the Catling Mindswipe Blog), was to go to the directory /etc/polkit-1/localauthority/50-local.d/ and create (it didn't exist in my Xubuntu setup) the file com.ubuntu.desktop.pkla (that's a lowercase 'L' in the extension and not the number '1'). You'll need to use sudo. Add the following content:
[Re-enable hibernate by default]
Identity=unix-user:*
Action=org.freedesktop.upower.hibernate
ResultActive=yes
Canonical didn't make it easy to re-enable.
Upon a new installation of Xubuntu 10.10, there weren't suspend or hibernate options in the shutdown menu. The first several hits on Ubuntu forums point to there not being enough swap space, but that wasn't the problem in my case. Doing a search for XFCE specifically (ignoring versions pre-4.6) came up with the following working solution from a blog at aldeby.org:
Repeat for ShowHibernate as necessary.
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