https://help.adobe.com/en_US/livecycle/11.0/DesignerScriptingRef/WS92d06802c76abadb-3e14850712a151d270d-7f19.2.html
Adobe LiveCycle ES4 * rootElement
adobe livecyclerootelement
https://api.flutter.dev/flutter/widgets/WidgetsBinding/rootElement.html
rootElement property - WidgetsBinding mixin - widgets library - Dart API
API docs for the rootElement property from the WidgetsBinding mixin, for the Dart programming language.
rootelementpropertymixinwidgetslibrary