diff --git a/aleksis/core/managers.py b/aleksis/core/managers.py
index 07237fdac02af7750a2000f89167cb9bbc217a5c..1c9266ab7cb65f8a2109ad4863fcc1a2614958c3 100644
--- a/aleksis/core/managers.py
+++ b/aleksis/core/managers.py
@@ -33,6 +33,12 @@ class CurrentSiteManagerWithoutMigrations(AlekSISBaseManager):
     use_in_migrations = False
 
 
+class AlekSISBaseManagerWithoutMigrations(AlekSISBaseManager):
+    """AlekSISBaseManager for auto-generating managers just by query sets."""
+
+    use_in_migrations = False
+
+
 class DateRangeQuerySetMixin:
     """QuerySet with custom query methods for models with date ranges.
 
@@ -139,7 +145,7 @@ class InstalledWidgetsDashboardWidgetOrderManager(Manager):
         return super().get_queryset().filter(widget_id__in=dashboard_widget_pks)
 
 
-class PolymorphicCurrentSiteManager(AlekSISBaseManager, PolymorphicManager):
+class PolymorphicCurrentSiteManager(AlekSISBaseManagerWithoutMigrations, PolymorphicManager):
     """Default manager for extensible, polymorphic models."""
 
 
diff --git a/aleksis/core/migrations/0055_oauthapplication_post_logout_redirect_uris.py b/aleksis/core/migrations/0049_oauthapplication_post_logout_redirect_uris.py
similarity index 91%
rename from aleksis/core/migrations/0055_oauthapplication_post_logout_redirect_uris.py
rename to aleksis/core/migrations/0049_oauthapplication_post_logout_redirect_uris.py
index 0d1232de9221a0c3173778230c0911fc87a14d49..a14526b2f0c32077e873c9b3bcd0cb21ee9e0cd6 100644
--- a/aleksis/core/migrations/0055_oauthapplication_post_logout_redirect_uris.py
+++ b/aleksis/core/migrations/0049_oauthapplication_post_logout_redirect_uris.py
@@ -7,7 +7,7 @@ import django.db.models.deletion
 class Migration(migrations.Migration):
     dependencies = [
         ("sites", "0002_alter_domain_unique"),
-        ("core", "0054_calendarevent_timezone"),
+        ("core", "0048_delete_personalicalurl"),
     ]
 
     operations = [
diff --git a/aleksis/core/migrations/0050_managed_by_app_label.py b/aleksis/core/migrations/0050_managed_by_app_label.py
new file mode 100644
index 0000000000000000000000000000000000000000..0de24ef5fe734d99c9c606b8b7b76a4167348190
--- /dev/null
+++ b/aleksis/core/migrations/0050_managed_by_app_label.py
@@ -0,0 +1,184 @@
+# Generated by Django 4.1.9 on 2023-07-06 21:10
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("sites", "0002_alter_domain_unique"),
+        ("core", "0049_oauthapplication_post_logout_redirect_uris"),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name="activity",
+            name="managed_by_app_label",
+            field=models.CharField(
+                blank=True,
+                editable=False,
+                max_length=255,
+                verbose_name="App label of app responsible for managing this instance",
+            ),
+        ),
+        migrations.AddField(
+            model_name="additionalfield",
+            name="managed_by_app_label",
+            field=models.CharField(
+                blank=True,
+                editable=False,
+                max_length=255,
+                verbose_name="App label of app responsible for managing this instance",
+            ),
+        ),
+        migrations.AddField(
+            model_name="announcement",
+            name="managed_by_app_label",
+            field=models.CharField(
+                blank=True,
+                editable=False,
+                max_length=255,
+                verbose_name="App label of app responsible for managing this instance",
+            ),
+        ),
+        migrations.AddField(
+            model_name="announcementrecipient",
+            name="managed_by_app_label",
+            field=models.CharField(
+                blank=True,
+                editable=False,
+                max_length=255,
+                verbose_name="App label of app responsible for managing this instance",
+            ),
+        ),
+        migrations.AddField(
+            model_name="custommenu",
+            name="managed_by_app_label",
+            field=models.CharField(
+                blank=True,
+                editable=False,
+                max_length=255,
+                verbose_name="App label of app responsible for managing this instance",
+            ),
+        ),
+        migrations.AddField(
+            model_name="custommenuitem",
+            name="managed_by_app_label",
+            field=models.CharField(
+                blank=True,
+                editable=False,
+                max_length=255,
+                verbose_name="App label of app responsible for managing this instance",
+            ),
+        ),
+        migrations.AddField(
+            model_name="dashboardwidgetorder",
+            name="managed_by_app_label",
+            field=models.CharField(
+                blank=True,
+                editable=False,
+                max_length=255,
+                verbose_name="App label of app responsible for managing this instance",
+            ),
+        ),
+        migrations.AddField(
+            model_name="datacheckresult",
+            name="managed_by_app_label",
+            field=models.CharField(
+                blank=True,
+                editable=False,
+                max_length=255,
+                verbose_name="App label of app responsible for managing this instance",
+            ),
+        ),
+        migrations.AddField(
+            model_name="group",
+            name="managed_by_app_label",
+            field=models.CharField(
+                blank=True,
+                editable=False,
+                max_length=255,
+                verbose_name="App label of app responsible for managing this instance",
+            ),
+        ),
+        migrations.AddField(
+            model_name="grouptype",
+            name="managed_by_app_label",
+            field=models.CharField(
+                blank=True,
+                editable=False,
+                max_length=255,
+                verbose_name="App label of app responsible for managing this instance",
+            ),
+        ),
+        migrations.AddField(
+            model_name="notification",
+            name="managed_by_app_label",
+            field=models.CharField(
+                blank=True,
+                editable=False,
+                max_length=255,
+                verbose_name="App label of app responsible for managing this instance",
+            ),
+        ),
+        migrations.AddField(
+            model_name="pdffile",
+            name="managed_by_app_label",
+            field=models.CharField(
+                blank=True,
+                editable=False,
+                max_length=255,
+                verbose_name="App label of app responsible for managing this instance",
+            ),
+        ),
+        migrations.AddField(
+            model_name="person",
+            name="managed_by_app_label",
+            field=models.CharField(
+                blank=True,
+                editable=False,
+                max_length=255,
+                verbose_name="App label of app responsible for managing this instance",
+            ),
+        ),
+        migrations.AddField(
+            model_name="persongroupthrough",
+            name="managed_by_app_label",
+            field=models.CharField(
+                blank=True,
+                editable=False,
+                max_length=255,
+                verbose_name="App label of app responsible for managing this instance",
+            ),
+        ),
+        migrations.AddField(
+            model_name="room",
+            name="managed_by_app_label",
+            field=models.CharField(
+                blank=True,
+                editable=False,
+                max_length=255,
+                verbose_name="App label of app responsible for managing this instance",
+            ),
+        ),
+        migrations.AddField(
+            model_name="schoolterm",
+            name="managed_by_app_label",
+            field=models.CharField(
+                blank=True,
+                editable=False,
+                max_length=255,
+                verbose_name="App label of app responsible for managing this instance",
+            ),
+        ),
+        migrations.AddField(
+            model_name="taskuserassignment",
+            name="managed_by_app_label",
+            field=models.CharField(
+                blank=True,
+                editable=False,
+                max_length=255,
+                verbose_name="App label of app responsible for managing this instance",
+            ),
+        ),
+    ]
diff --git a/aleksis/core/migrations/0051_calendarevent_and_holiday.py b/aleksis/core/migrations/0051_calendarevent_and_holiday.py
index 28e5294027d766f64d6cb644696e84f7a9c2a6ac..76d64c0e605d5a0f5485760ea9b6cd046840c818 100644
--- a/aleksis/core/migrations/0051_calendarevent_and_holiday.py
+++ b/aleksis/core/migrations/0051_calendarevent_and_holiday.py
@@ -97,7 +97,6 @@ class Migration(migrations.Migration):
             },
             bases=(aleksis.core.mixins.CalendarEventMixin, models.Model),
             managers=[
-                ("objects", aleksis.core.managers.PolymorphicCurrentSiteManager()),
             ],
         ),
         migrations.CreateModel(
@@ -122,7 +121,6 @@ class Migration(migrations.Migration):
             },
             bases=("core.calendarevent",),
             managers=[
-                ("objects", aleksis.core.managers.PolymorphicCurrentSiteManager()),
             ],
         ),
         migrations.AddConstraint(
diff --git a/aleksis/core/migrations/0056_alter_activity_managers_and_more.py b/aleksis/core/migrations/0052_site_related_name.py
similarity index 99%
rename from aleksis/core/migrations/0056_alter_activity_managers_and_more.py
rename to aleksis/core/migrations/0052_site_related_name.py
index 3edabd1c674c8a30dcc2c60b06bc4bac931bb544..9d67918504811dfb12d4ae4acbf2f800263f83ea 100644
--- a/aleksis/core/migrations/0056_alter_activity_managers_and_more.py
+++ b/aleksis/core/migrations/0052_site_related_name.py
@@ -1,265 +1,17 @@
-# Generated by Django 4.1.9 on 2023-06-30 11:36
+# Generated by Django 4.1.10 on 2023-07-20 20:35
 
-import aleksis.core.managers
 from django.db import migrations, models
 import django.db.models.deletion
 
 
 class Migration(migrations.Migration):
+
     dependencies = [
         ("sites", "0002_alter_domain_unique"),
-        ("core", "0055_oauthapplication_post_logout_redirect_uris"),
+        ("core", "0051_calendarevent_and_holiday"),
     ]
 
     operations = [
-        migrations.AlterModelManagers(
-            name="activity",
-            managers=[
-                ("objects", aleksis.core.managers.AlekSISBaseManager()),
-            ],
-        ),
-        migrations.AlterModelManagers(
-            name="additionalfield",
-            managers=[
-                ("objects", aleksis.core.managers.AlekSISBaseManager()),
-            ],
-        ),
-        migrations.AlterModelManagers(
-            name="announcementrecipient",
-            managers=[
-                ("objects", aleksis.core.managers.AlekSISBaseManager()),
-            ],
-        ),
-        migrations.AlterModelManagers(
-            name="custommenu",
-            managers=[
-                ("objects", aleksis.core.managers.AlekSISBaseManager()),
-            ],
-        ),
-        migrations.AlterModelManagers(
-            name="custommenuitem",
-            managers=[
-                ("objects", aleksis.core.managers.AlekSISBaseManager()),
-            ],
-        ),
-        migrations.AlterModelManagers(
-            name="datacheckresult",
-            managers=[
-                ("objects", aleksis.core.managers.AlekSISBaseManager()),
-            ],
-        ),
-        migrations.AlterModelManagers(
-            name="grouptype",
-            managers=[
-                ("objects", aleksis.core.managers.AlekSISBaseManager()),
-            ],
-        ),
-        migrations.AlterModelManagers(
-            name="notification",
-            managers=[
-                ("objects", aleksis.core.managers.AlekSISBaseManager()),
-            ],
-        ),
-        migrations.AlterModelManagers(
-            name="pdffile",
-            managers=[
-                ("objects", aleksis.core.managers.AlekSISBaseManager()),
-            ],
-        ),
-        migrations.AlterModelManagers(
-            name="person",
-            managers=[
-                ("objects", aleksis.core.managers.AlekSISBaseManager()),
-            ],
-        ),
-        migrations.AlterModelManagers(
-            name="persongroupthrough",
-            managers=[
-                ("objects", aleksis.core.managers.AlekSISBaseManager()),
-            ],
-        ),
-        migrations.AlterModelManagers(
-            name="room",
-            managers=[
-                ("objects", aleksis.core.managers.AlekSISBaseManager()),
-            ],
-        ),
-        migrations.AlterModelManagers(
-            name="taskuserassignment",
-            managers=[
-                ("objects", aleksis.core.managers.AlekSISBaseManager()),
-            ],
-        ),
-        migrations.AddField(
-            model_name="activity",
-            name="managed_by_app_label",
-            field=models.CharField(
-                blank=True,
-                editable=False,
-                max_length=255,
-                verbose_name="App label of app responsible for managing this instance",
-            ),
-        ),
-        migrations.AddField(
-            model_name="additionalfield",
-            name="managed_by_app_label",
-            field=models.CharField(
-                blank=True,
-                editable=False,
-                max_length=255,
-                verbose_name="App label of app responsible for managing this instance",
-            ),
-        ),
-        migrations.AddField(
-            model_name="announcement",
-            name="managed_by_app_label",
-            field=models.CharField(
-                blank=True,
-                editable=False,
-                max_length=255,
-                verbose_name="App label of app responsible for managing this instance",
-            ),
-        ),
-        migrations.AddField(
-            model_name="announcementrecipient",
-            name="managed_by_app_label",
-            field=models.CharField(
-                blank=True,
-                editable=False,
-                max_length=255,
-                verbose_name="App label of app responsible for managing this instance",
-            ),
-        ),
-        migrations.AddField(
-            model_name="custommenu",
-            name="managed_by_app_label",
-            field=models.CharField(
-                blank=True,
-                editable=False,
-                max_length=255,
-                verbose_name="App label of app responsible for managing this instance",
-            ),
-        ),
-        migrations.AddField(
-            model_name="custommenuitem",
-            name="managed_by_app_label",
-            field=models.CharField(
-                blank=True,
-                editable=False,
-                max_length=255,
-                verbose_name="App label of app responsible for managing this instance",
-            ),
-        ),
-        migrations.AddField(
-            model_name="dashboardwidgetorder",
-            name="managed_by_app_label",
-            field=models.CharField(
-                blank=True,
-                editable=False,
-                max_length=255,
-                verbose_name="App label of app responsible for managing this instance",
-            ),
-        ),
-        migrations.AddField(
-            model_name="datacheckresult",
-            name="managed_by_app_label",
-            field=models.CharField(
-                blank=True,
-                editable=False,
-                max_length=255,
-                verbose_name="App label of app responsible for managing this instance",
-            ),
-        ),
-        migrations.AddField(
-            model_name="group",
-            name="managed_by_app_label",
-            field=models.CharField(
-                blank=True,
-                editable=False,
-                max_length=255,
-                verbose_name="App label of app responsible for managing this instance",
-            ),
-        ),
-        migrations.AddField(
-            model_name="grouptype",
-            name="managed_by_app_label",
-            field=models.CharField(
-                blank=True,
-                editable=False,
-                max_length=255,
-                verbose_name="App label of app responsible for managing this instance",
-            ),
-        ),
-        migrations.AddField(
-            model_name="notification",
-            name="managed_by_app_label",
-            field=models.CharField(
-                blank=True,
-                editable=False,
-                max_length=255,
-                verbose_name="App label of app responsible for managing this instance",
-            ),
-        ),
-        migrations.AddField(
-            model_name="pdffile",
-            name="managed_by_app_label",
-            field=models.CharField(
-                blank=True,
-                editable=False,
-                max_length=255,
-                verbose_name="App label of app responsible for managing this instance",
-            ),
-        ),
-        migrations.AddField(
-            model_name="person",
-            name="managed_by_app_label",
-            field=models.CharField(
-                blank=True,
-                editable=False,
-                max_length=255,
-                verbose_name="App label of app responsible for managing this instance",
-            ),
-        ),
-        migrations.AddField(
-            model_name="persongroupthrough",
-            name="managed_by_app_label",
-            field=models.CharField(
-                blank=True,
-                editable=False,
-                max_length=255,
-                verbose_name="App label of app responsible for managing this instance",
-            ),
-        ),
-        migrations.AddField(
-            model_name="room",
-            name="managed_by_app_label",
-            field=models.CharField(
-                blank=True,
-                editable=False,
-                max_length=255,
-                verbose_name="App label of app responsible for managing this instance",
-            ),
-        ),
-        migrations.AddField(
-            model_name="schoolterm",
-            name="managed_by_app_label",
-            field=models.CharField(
-                blank=True,
-                editable=False,
-                max_length=255,
-                verbose_name="App label of app responsible for managing this instance",
-            ),
-        ),
-        migrations.AddField(
-            model_name="taskuserassignment",
-            name="managed_by_app_label",
-            field=models.CharField(
-                blank=True,
-                editable=False,
-                max_length=255,
-                verbose_name="App label of app responsible for managing this instance",
-            ),
-        ),
         migrations.AlterField(
             model_name="activity",
             name="site",
diff --git a/aleksis/core/migrations/0057_calendar_event_add_managed_by_app_label.py b/aleksis/core/migrations/0057_calendar_event_add_managed_by_app_label.py
deleted file mode 100644
index 4b40bcd9533169ff86fe7a8ab5e794672fbcc8a5..0000000000000000000000000000000000000000
--- a/aleksis/core/migrations/0057_calendar_event_add_managed_by_app_label.py
+++ /dev/null
@@ -1,22 +0,0 @@
-# Generated by Django 4.1.9 on 2023-07-05 13:04
-
-from django.db import migrations, models
-
-
-class Migration(migrations.Migration):
-    dependencies = [
-        ("core", "0056_alter_activity_managers_and_more"),
-    ]
-
-    operations = [
-        migrations.AddField(
-            model_name="calendarevent",
-            name="managed_by_app_label",
-            field=models.CharField(
-                blank=True,
-                editable=False,
-                max_length=255,
-                verbose_name="App label of app responsible for managing this instance",
-            ),
-        ),
-    ]
diff --git a/aleksis/core/schema/__init__.py b/aleksis/core/schema/__init__.py
index 3279e7b12e31318a190c0d2fa738be8fc2dc1eaa..a1c2896ef44220326d851e81ba53037db3a70588 100644
--- a/aleksis/core/schema/__init__.py
+++ b/aleksis/core/schema/__init__.py
@@ -142,7 +142,7 @@ class Query(graphene.ObjectType):
         return get_objects_for_user(info.context.user, "core.view_group", Group)
 
     @staticmethod
-    def resolve_group_by_id(root, info, id): # noqa
+    def resolve_group_by_id(root, info, id):  # noqa
         group = Group.objects.filter(id=id)
 
         if len(group) != 1: