The classic menu indicator is now available to Ubuntu 12.04 LTS Precise Pangolin and the earlier releases Oneiric and Natty as well. It will add a quite similar Gnome classic menu with sub menus for applications and system settings menus. Install Classic Menu Indicator in Ubuntu 12.04 Precise Pangolin/11.10 Oneiric/11.04 Natty
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Installation of Classic Indicator, open Terminal and enter following commands:
sudo apt-add-repository ppa:diesch/testing sudo apt-get update sudo apt-get install
Now Press Alt+F2 and enter following command to start indicator:
classicmenu-indicator