Prevent duplicate action registration in register_model_actions()

netbox/utilities/permissions.py

@@ -53,7 +53,8 @@ def register_model_actions(model: type[Model], actions: list[ModelAction | str])
     for action in actions:
         if isinstance(action, str):
             action = ModelAction(name=action)
-        registry['model_actions'][label].append(action)
+        if action not in registry['model_actions'][label]:
+            registry['model_actions'][label].append(action)
 
 
 def get_permission_for_model(model, action):

netbox/utilities/tests/test_permissions.py

@@ -80,6 +80,12 @@ class RegisterModelActionsTest(TestCase):
         self.assertEqual(actions[0].name, 'first')
         self.assertEqual(actions[1].name, 'second')
 
+    def test_duplicate_registration_ignored(self):
+        register_model_actions(Site, [ModelAction('sync')])
+        register_model_actions(Site, [ModelAction('sync', help_text='Different help')])
+        actions = registry['model_actions']['dcim.site']
+        self.assertEqual(len(actions), 1)
+
 
 class ObjectPermissionFormTest(TestCase):