Slicer can now display 3D, slice, plot, etc. views in multiple windows and not just in the main application window - see 1-minute demo video.
Display views in separate windows - can be dragged to a second screen or additional touchscreen or drawing tablet:
The extra window can be displayed floating over the application window as “picture-in-picture”:
The additional window can be also docked into application window (any corners or sides):
Views can be maximized/restored independently in each window.
Currently, only a single additional layout is added, which adds one extra window. Custom views can be specified by an XML description (see example description and code).