OptionalcreatedOptionalgapVertical gap in world units. When omitted, the spacing at link creation is preserved.
OptionalmetadataOptionalsyncResize the upper component when the lower width changes.
OptionalupperMaximum world width restored when the lower component grows again.
OptionalwidthHorizontal world axis used as the synchronized width. Defaults to auto.
Persistent vertical relation between two component instances.
The upper component is centered above the lower component and follows its width while never exceeding
upperMaxWidth. This is intentionally separate from catalog anchors: it can link any two placed instances without requiring model-specific connection points.