Angular 1.6.1 Auto-stringify IE 11 bug

HTML

<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.6.1/angular.js"></script>
<script src="https://code.angularjs.org/1.6.1/angular-animate.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/babel-polyfill/6.22.0/polyfill.js"></script>
<div ng-app="testApp">
    {{$root.object}}
</div>

JavaScript

var app = angular.module('testApp', []);

app.run(['$rootScope',  function($rootScope) {
    $rootScope.object = { a: 'a', b: 'b'};
}])