The ids a definition opens, its own edges and its items' — the one walk of
the edge brand both this set and the tab-stack union read, so a screen an
edge targets cannot be in one and not the other. An action edge names its
target by id only (its table is not the definition's actions), so the walk
carries ids beside definitions; the reachable set reads both.
The ids a definition opens, its own edges and its items' — the one walk of the edge brand both this set and the tab-stack union read, so a screen an edge targets cannot be in one and not the other. An action edge names its target by id only (its table is not the definition's actions), so the walk carries ids beside definitions; the reachable set reads both.