In 13.04, I enabled hibernation by following these instructions:

You can also enable the hibernate option in the menus. To do that, use your favorite text editor to create /etc/polkit-1/localauthority/50-local.d/com.ubuntu.enable-hibernate.pkla. Add the following to the file and save:

[Re-enable hibernate by default]

It worked fine in 13.04, but after upgrading to 13.10, the "hibernate" option no longer appears in the top right corner shutdown/login menu and neither in the menu that comes up when I press the laptop's power button (image here). Yes, I have checked that the the .pkla file is still there untouched. What could be the problem?

Hibernate itself still works when I do it from the terminal with pm-hibernate.

Edit: similar question: Hibernation is still missing from menu in 13.10 after enabling via polkit. How to enable?