The Output Bar, Control Centre and Properties Bar are all pinned bars that must be placed between the toolbars and the drawing area.
These bars have three possible states.
In the example below the Control Centre is pinned to be visible permanently.
If it is unpinned, it will fold up to the side of the main window and unfold itself when the cursor is positioned over the Control Centre tab.
The bar is not attached to the main frame but can be positioned anywhere on the display.