This doesn’t work:2.Inserting an Edge LoopEdge loop insertion using Gizmo 3D can be done using the Scale manipulators. This quickly creates topology inserts on a model rather than a simple extrusion. As with the Extrude feature, the model must be a PolyMesh or DynaMesh and cannot have subdivi*sion levels.
While Gizmo 3D is active, holding the CTRL key and dragging the Gizmo 3D Scale manipulator will create an edge loop along the boundary of the non-masked part of the model.
Of course, it is possible to simply CTRL+ click the appropriate Scale manipulator to create an edge loop. Take care when doing this; the inserted edge loop won’t be visible and you run a risk of overlapping edges.
When holding control it’s clipping geometry and not inserting loop.