In AngularJS we were able to trigger a digest cycle by getting the ng-app element with something like
var scope = angular.element(element).scope(); scope.$
I usually do it as follows in dev mode
ng.probe(getAllAngularRootElements()[0]).injector.get(ng.coreTokens.ApplicationRef).tick()
Starting with Angular 9 with Ivy you can call:
ng.applyChanges(ng.getComponent($0))
Where $0 points to component's element
$0