- A fold's zone clipped across the root of a tab folded before on the same
line kept a sliver of no width there, which made the zone look like it
crossed a slanted edge. The one real piece is the zone now (#638).
- When the tabs a fold line spans can't take the side beyond them along,
because it joins the side that stays through other material (a tab on the
inside edge of an L, the fixed point on the far leg), the tabs' own ends fold
instead, the same part as with the fixed point on the near leg (#639).
Co-authored-by: jonaswre <3731681+jonaswre@users.noreply.github.com>
Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>
