Extrude Multiple will be available from 3.8.4
Extrude tool is one of the most frequently used tool in Designer Tool but it allows only one polygon to be extruded in a normal direction of it.
So In order to overcome this limitation Extrude Multiple has been added to support extruding multiple polygons in individual normal directions, average or x/y/z direction.
Left : Selected multiple polygons
Right : Extruded polygons in individual directions with Extrude Multiple