This functionality is only available for certain module packages. Info

Auxiliary Objects

Auxiliary objects are available in both the workspace and the workdesk. They are used to help during placement of an item in the workspace or workdesk. Auxiliary objects include points, lines, planes, and coordinate systems. When placing an auxiliary object it can be snapped to an existing object, and a constraint is created. When an item is placed onto an auxiliary object, a constraint is automatically created, too.

Placed items can be snapped to: