offstage property
Whether this widget is in the tree but not on the screen.
True for content nobody can see or touch: a route kept alive under the
one that covers it, an Offstage/Visibility(visible: false) subtree,
the hidden children of an IndexedStack. Such nodes keep their
last-laid-out layout — stale rects that overlap the visible screen
— which is why InspectTree.nodeAtPoint skips them and the tree view
folds them away by default. See guest_inspect.dart for how it is
detected; the VM-service path (run) cannot detect it and leaves this
false.
Implementation
final bool offstage;