Null check operator used on a null value
main.dart.js:78776 at DevToolsScaffoldState__setupTabController_closure0.call$0 (http://127.0.0.1:9108/main.dart.js:119574:22)
main.dart.js:78776 at TabController.notifyListeners$0 (http://127.0.0.1:9108/main.dart.js:192944:16)
main.dart.js:78776 at TabController._changeIndex$3$curve$duration (http://127.0.0.1:9108/main.dart.js:216549:15)
main.dart.js:78776 at TabController.animateTo$1 (http://127.0.0.1:9108/main.dart.js:216567:12)
main.dart.js:78776 at DevToolsScaffoldState.didUpdateWidget$1 (http://127.0.0.1:9108/main.dart.js:119455:32)
main.dart.js:78776 at StatefulElement.update$1 (http://127.0.0.1:9108/main.dart.js:258887:10)
main.dart.js:78776 at _InheritedProviderScopeElement.updateChild$3 (http://127.0.0.1:9108/main.dart.js:258244:19)
main.dart.js:78776 at _InheritedProviderScopeElement.performRebuild$0 (http://127.0.0.1:9108/main.dart.js:258819:41)
main.dart.js:78776 at _InheritedProviderScopeElement.rebuild$1$force (http://127.0.0.1:9108/main.dart.js:258703:14)
main.dart.js:78776 at _InheritedProviderScopeElement.update$1 (http://127.0.0.1:9108/main.dart.js:258931:13)
