wp details controller informs parent to update back URL

app/assets/javascripts/angular/work_packages/controllers/work-package-details-controller.js

@@ -86,6 +86,9 @@ angular.module('openproject.workPackages.controllers')
     }
     $scope.refreshWorkPackage = refreshWorkPackage; // expose to child controllers
 
+    // Inform parent that work package is loaded so back url can be maintained
+    $scope.$emit('workPackgeLoaded');
+
     function outputMessage(message, isError) {
       $scope.$emit('flashMessage', {
         isError: !!isError,

app/assets/javascripts/angular/work_packages/controllers/work-packages-list-controller.js

@@ -264,6 +264,10 @@ angular.module('openproject.workPackages.controllers')
     }
   });
 
+  $rootScope.$on('workPackgeLoaded', function(event, message) {
+    $scope.maintainBackUrl();
+  });
+
   $scope.openLatestTab = function() {
     $state.go(latestTab.getStateName(), { workPackageId: $scope.preselectedWorkPackageId });
   };