OptionalclassOptionalcoreOptionalcyOptionalinitialVR-5 (owner verification 2026-07-26): the layout the SHELL mounted the canvas with, so the dropdown reflects reality (the Hierarchy tab laid out hierarchic while the dropdown said force directed). Toolbar layout ids: force, hierarchy, circle, grid, concentric.
The Cytoscape instance from CytoscapeCanvas
onReady; null (or omitted) until the canvas mounts, and every control no-ops until a live handle arrives. The same prop name every handle-taking component uses (issue #18).