Stack

Stack allows you to copy blocks in a row or grid

Selecting a region

Refer to Move

Stacking

Start scrolling in a direction to stack the region end-to-end

Scrolling in another direction will turn it from a 1D stack into a 2D stack, and scrolling in all 3 dimensions will perform a 3D stack

To confirm the stack, use Right Click

To undo/redo the action, use Ctrl+Z/Ctrl+Y

See below for a demonstration