Unity 2D Updated for Ubuntu 12.04, 11.10 and 11.04

The update fixes a bug in Unity 2D that was exposed by the Mozilla Firefox 13.0 update issued by Canonical last week, which resulted in Firefox being unable to open popup menus. The bug can be fixed if you upgrade your system(s) to version 5.12.0-0ubuntu1.1 for Ubuntu 12.04 LTS, 4.12.0-0ubuntu1.2 for Ubuntu 11.10, and for Ubuntu 11.04. To apply the update, run the Update Manager.