Customization
These panels can be populated with other completely customizable menus and buttons, including new menus, search boxes, and icons, with the icons in particular (called launchers) performing functions similar to the quick-launch feature found in the Microsoft Windows 98–Vista taskbar. In GNOME 2.x, this was accomplished by right-clicking on an applet and selecting options from a menu; in GNOME 3.x, one must press the Alt key while right-clicking to attain the same functionality.
Other applications can also be attached to the panels, and the panels are highly reconfigurable: anything on these panels can be moved, removed, or configured in other ways. For example, a migrating Microsoft Windows user might move the menus usually positioned in the top panel into a 'start' menu on the bottom panel as well as moving the notification area into the place normally positioned by the Windows notification area, then remove the top panel altogether, to interact with GNOME Panel similarly to the Windows taskbar.
The version of GNOME Panel available in the repository for Ubuntu 12.04 is a modified version of Fallback Mode with the addition of a custom theme and ports of Ubuntu's own Indicators from their old GNOME 2.x desktop. Trisquel GNU/Linux also uses a modified Fallback Mode for its main desktop, as some free software drivers do not support 3D acceleration.
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