If you check this option and double-click a product or representation,
that does not belong to the active level, it becomes UI-active (blue highlighted)
in the specification tree, its children are displayed normally in the geometry
space and the other objects are in low-light in the geometry space.

Low-light of the node that does not belong to the active level
If you double-click another product or representation, it immediately
becomes highlighted, and the others elements are dimmed.

By default, this option is not selected.