Here's how you can enable hibernation on your Ubuntu 12.04 computer. 1. Open a terminal window. 2. Type in the following command, then hit Enter. sudo gedit /var/lib/polkit-1/localauthority/50-local.d/hibernate.pkla 3. Paste in the following text: [Re-enable Hibernate] Identity=unix-user:* Action=org.freedesktop.upower.hibernate ResultActive=yes 4. Restart your computer.
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Ubuntu Tweaks | Noobslab