Here's how you can enable ALT-TAB in GNOME Classic in Ubuntu 12.10. To install GNOME Classic: 1. Open a terminal window. 2. Type in the following command then hit Enter. sudo apt-get install gnome-shell 3. Log out and choose GNOME Classic on the login screen. To Install and use CCSM: 1. Open a terminal window. 2. Type in the following command then hit Enter. sudo apt-get install compizconfig-settings-manager compiz-plugins 3. Use this command to start CCSM: ccsm 4. Click Window Management in the left pane. 5. In the right side, Click the checkbox next to Application Switcher. That's it. ALT-TAB should now work for you in GNOME Classic.
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