as stated several times - there are to many inconsistencies - this is one of them:
left surface
with a gumball Extrude the result of a surface is a solid.
right subd
gumball extruding a full subD will result in an open subD.
i see, that this is the desired behaviour for a few / partial number of faces. But it is inconsistent for the entire subD.
Expected / Wish
Gumball extrude for surfaces / subD should result in comparable results.
I would love to see a default behaviour without additional hotkeys:
extrude a full object resulting in a closed object. (both Surface / PolySurface / SubD)
As Gumball is already rich of hotkeys - extrude with hotkey should give a copy behaviour (hotkey option) → resulting in a new, closed object if only a partial object is selected. input faces / surfaces are copied and treated as “extrude full object”
this would make @theoutside the paper-doll Workflow even nicer ;-D
kind regards - tom