From Synfig Studio :: Documentation
Synfig Studio has a comprehensive dock system. The panels (and the Canvas) can be docked or panned. It means that you can group then in vertical or horizontal dock windows and/or place them up, down to the left or to the right. Just drag and drop by the Panel tab and put it down on another dock or place it using the Placement Widget.
In Synfig Studio, the panels list and predefined workspaces can be found in the Window Menu.