Here's how you can upgrade to GNOME 3.8 in Ubuntu 13.04. 1. Open a terminal window. 2. Type in the following commands then hit Enter after each. sudo add-apt-repository ppa:gnome3-team/gnome3 sudo apt-get update && sudo apt-get install gnome-shell ubuntu-gnome-desktop (use this command if you don't have GNOME Shell installed) sudo apt-get update && sudo apt-get dist-upgrade (use this command if you do have GNOME Shell installed) 3. Reboot your Ubuntu 13.04 system and login.
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How To Upgrade to GNOME 3.8 in Ubuntu 13.04 | OMG Ubuntu!