I need unset up the Trash button on bottom the Pane, and set up these for Workplaces button. And I prefer for using set up Main Button on Dock, analogically them. I.e. using it for permanently displaying Main button on top of the Pane. Other dock's button set, - such any application's buttons who set to Dock or present them as running apps now, - it's can be present as floating and rolling, as it's have been uses currently. How can I change this behavior on the Dock under Ubuntu 12.04 LTS? Any ideas?