diff --git a/src/Bundle/ChillActivityBundle/Controller/ActivityController.php b/src/Bundle/ChillActivityBundle/Controller/ActivityController.php
index c116c5d35..1dae24464 100644
--- a/src/Bundle/ChillActivityBundle/Controller/ActivityController.php
+++ b/src/Bundle/ChillActivityBundle/Controller/ActivityController.php
@@ -209,14 +209,14 @@ class ActivityController extends AbstractController
             throw $this->createNotFoundException('Template not found');
         }
 
-        $activity_json = $this->serializer->serialize($entity, 'json', ['groups' => 'read']);
+        $activity_array = $this->serializer->normalize($entity, 'json', ['groups' => 'read']);
         
         return $this->render($view, [
             'person'   => $person,
             'accompanyingCourse' => $accompanyingPeriod,
             'entity' => $entity,
             'form' => $form->createView(),
-            'activity_json' => $activity_json
+            'activity_json' => $activity_array
         ]);
     }
 
@@ -323,7 +323,7 @@ class ActivityController extends AbstractController
             throw $this->createNotFoundException('Template not found');
         }
 
-        $activity_json = $this->serializer->serialize($entity, 'json', ['groups' => ['read']]);
+        $activity_array = $this->serializer->normalize($entity, 'json', ['groups' => 'read']);
          
         return $this->render($view, array(
             'entity'      => $entity,
@@ -331,7 +331,7 @@ class ActivityController extends AbstractController
             'delete_form' => $deleteForm->createView(),
             'person' => $person,
             'accompanyingCourse' => $accompanyingPeriod,
-            'activity_json' => $activity_json
+            'activity_json' => $activity_array
         ));
     }
 
diff --git a/src/Bundle/ChillActivityBundle/Entity/Activity.php b/src/Bundle/ChillActivityBundle/Entity/Activity.php
index 0b35d961e..5834cd7cd 100644
--- a/src/Bundle/ChillActivityBundle/Entity/Activity.php
+++ b/src/Bundle/ChillActivityBundle/Entity/Activity.php
@@ -34,6 +34,7 @@ use Chill\MainBundle\Entity\HasScopeInterface;
 use Doctrine\Common\Collections\Collection;
 use Doctrine\Common\Collections\ArrayCollection;
 use Chill\MainBundle\Validator\Constraints\Entity\UserCircleConsistency;
+use Symfony\Component\Serializer\Annotation\Groups;
 
 /**
  * Class Activity
@@ -61,6 +62,7 @@ class Activity implements HasCenterInterface, HasScopeInterface
      * @ORM\Id
      * @ORM\Column(name="id", type="integer")
      * @ORM\GeneratedValue(strategy="AUTO")
+     * @Groups({"read"})
      */
     private ?int $id;
 
@@ -121,11 +123,13 @@ class Activity implements HasCenterInterface, HasScopeInterface
 
     /**
      * @ORM\ManyToMany(targetEntity="Chill\PersonBundle\Entity\Person")
+     * @Groups({"read"})
      */
     private Collection $persons;
 
     /**
      * @ORM\ManyToMany(targetEntity="Chill\ThirdPartyBundle\Entity\ThirdParty")
+     * @Groups({"read"})
      */
     private Collection $thirdParties;
 
@@ -136,6 +140,7 @@ class Activity implements HasCenterInterface, HasScopeInterface
 
     /**
      * @ORM\ManyToMany(targetEntity="Chill\MainBundle\Entity\User")
+     * @Groups({"read"})
      */
     private Collection $users;
 
diff --git a/src/Bundle/ChillActivityBundle/Resources/views/Activity/editPerson.html.twig b/src/Bundle/ChillActivityBundle/Resources/views/Activity/editPerson.html.twig
index b0cfa13c2..733912375 100644
--- a/src/Bundle/ChillActivityBundle/Resources/views/Activity/editPerson.html.twig
+++ b/src/Bundle/ChillActivityBundle/Resources/views/Activity/editPerson.html.twig
@@ -29,7 +29,7 @@
     <script src="{{ asset('build/async_upload.js') }}" type="text/javascript"></script>
     <script type="text/javascript">
         chill.displayAlertWhenLeavingModifiedForm('form[name="{{ edit_form.vars.form.vars.name }}"]', '{{ "You are going to leave a page with unsubmitted data. Are you sure you want to leave ?"|trans }}');
-        window.activity = {{ activity_json|e('js') }};
+        window.activity = {{ activity_json|json_encode|raw }};
     </script>
     {{ encore_entry_script_tags('vue_activity') }}
 {% endblock %}
diff --git a/src/Bundle/ChillActivityBundle/Resources/views/Activity/newPerson.html.twig b/src/Bundle/ChillActivityBundle/Resources/views/Activity/newPerson.html.twig
index 335b986c7..84f3f5ac3 100644
--- a/src/Bundle/ChillActivityBundle/Resources/views/Activity/newPerson.html.twig
+++ b/src/Bundle/ChillActivityBundle/Resources/views/Activity/newPerson.html.twig
@@ -13,7 +13,7 @@
     <script src="{{ asset('build/async_upload.js') }}" type="text/javascript"></script>
     <script type="text/javascript">
         chill.displayAlertWhenLeavingUnsubmittedForm('form[name="{{ form.vars.form.vars.name }}"]', '{{ "You are going to leave a page with unsubmitted data. Are you sure you want to leave ?"|trans }}');
-        window.activity = {{ activity_json|e('js') }};
+        window.activity = {{ activity_json|json_encode|raw }};
     </script>
     {{ encore_entry_script_tags('vue_activity') }}
 {% endblock %}