This command is a useful tool for editing 3D polylines within the drawings.
Procedure:
1. Run the "Polyline Editor" command.
2. Select 3D polyline in the drawing. Right after selecting one of the polylines of the drawing, this will be added to the Entities list located on the left-hand side of the »3D polyline editor« dialog.
3. Click on a polyline in the Entity list.