Ranked 0, like a new row: WithPlacementPreview already drops whatever it replaces, so
it competes with nothing, and on a SortKey tie it draws after the panels already there, as
the saved row will. A spec with no key of its own takes the derived one, or
PLACEMENT_PREVIEW_KEY.
The previewed spec as a registration.
Ranked 0, like a new row: WithPlacementPreview already drops whatever it replaces, so it competes with nothing, and on a
SortKeytie it draws after the panels already there, as the saved row will. A spec with no key of its own takes the derived one, or PLACEMENT_PREVIEW_KEY.