Hi Andrei,

> Michael, What do you think if it will automaticly "disable base surface" if you
> extrude frome surface, joined surface and edges?

Probably not for individual surface or edges since those can often be used for just regular simple extrudes where people are trying to generate a solid, but I think that it might work ok for the case of extruding a face that's a part of a joined surface.

- Michael