The mask coats the trace walls
A follow-up to 1.26.0's drape, from the same user's macro lens: the
stepped drape's raised piece overhung each copper edge with an open
underside — at millimetre range the mask read as a little roof peeling
off the substrate, arguably worse than the hover it replaced.
Rebuilt as two overlapping solids instead of a partition. The whole
film sits at the dropped level, hugging the laminate and tunnelling
straight through the copper (buried inside an opaque solid, so
harmless — and it has no wall at the copper boundary, so nothing is
coplanar with anything). Over copper, a full-height climb piece runs
from the film's bottom clear to its proper top, so the mask encases
the trace's top and side walls — which is what conformal mask
actually does. Trace and pad edges now render as a coated green
shoulder; mask openings are rimmed the way a real board's are.
Silkscreen keeps the partition from 1.26.0: ink is opaque and sits on
the local mask surface, and its pieces' walls never overlap in Z.