diff --git a/src/Umbraco.Core/Collections/EventClearingObservableCollection.cs b/src/Umbraco.Core/Collections/EventClearingObservableCollection.cs
index 724261ed8f..af25cc1b4a 100644
--- a/src/Umbraco.Core/Collections/EventClearingObservableCollection.cs
+++ b/src/Umbraco.Core/Collections/EventClearingObservableCollection.cs
@@ -8,7 +8,7 @@ namespace Umbraco.Core.Collections
     /// Allows clearing all event handlers
     /// </summary>
     /// <typeparam name="TValue"></typeparam>
-    public class EventClearingObservableCollection<TValue> : ObservableCollection<TValue>
+    public class EventClearingObservableCollection<TValue> : ObservableCollection<TValue>, INotifyCollectionChanged
     {
         public EventClearingObservableCollection()
         {
@@ -22,12 +22,20 @@ namespace Umbraco.Core.Collections
         {
         }
 
-        // need to override to clear
-        public override event NotifyCollectionChangedEventHandler CollectionChanged;
+        // need to explicitly implement with event accessor syntax in order to override in order to to clear
+        // c# events are weird, they do not behave the same way as other c# things that are 'virtual',
+        // a good article is here: https://medium.com/@unicorn_dev/virtual-events-in-c-something-went-wrong-c6f6f5fbe252
+        // and https://stackoverflow.com/questions/2268065/c-sharp-language-design-explicit-interface-implementation-of-an-event
+        private NotifyCollectionChangedEventHandler _changed;
+        event NotifyCollectionChangedEventHandler INotifyCollectionChanged.CollectionChanged
+        {
+            add { _changed += value; }
+            remove { _changed -= value; }
+        }
 
         /// <summary>
         /// Clears all event handlers for the <see cref="CollectionChanged"/> event
         /// </summary>
-        public void ClearCollectionChangedEvents() => CollectionChanged = null;
+        public void ClearCollectionChangedEvents() => _changed = null;
     }
 }
diff --git a/src/Umbraco.Core/Collections/ObservableDictionary.cs b/src/Umbraco.Core/Collections/ObservableDictionary.cs
index c7d1908d45..fd9e469f07 100644
--- a/src/Umbraco.Core/Collections/ObservableDictionary.cs
+++ b/src/Umbraco.Core/Collections/ObservableDictionary.cs
@@ -18,7 +18,7 @@ namespace Umbraco.Core.Collections
     /// </remarks>
     /// <typeparam name="TValue">The type of elements contained in the BindableCollection</typeparam>
     /// <typeparam name="TKey">The type of the indexing key</typeparam>
-    public class ObservableDictionary<TKey, TValue> : ObservableCollection<TValue>, IReadOnlyDictionary<TKey, TValue>, IDictionary<TKey, TValue>
+    public class ObservableDictionary<TKey, TValue> : ObservableCollection<TValue>, IReadOnlyDictionary<TKey, TValue>, IDictionary<TKey, TValue>, INotifyCollectionChanged
     {
         protected Dictionary<TKey, int> Indecies { get; }
         protected Func<TValue, TKey> KeySelector { get; }
@@ -77,13 +77,21 @@ namespace Umbraco.Core.Collections
 
         #endregion
 
-        // need to override to clear
-        public override event NotifyCollectionChangedEventHandler CollectionChanged;
+        // need to explicitly implement with event accessor syntax in order to override in order to to clear
+        // c# events are weird, they do not behave the same way as other c# things that are 'virtual',
+        // a good article is here: https://medium.com/@unicorn_dev/virtual-events-in-c-something-went-wrong-c6f6f5fbe252
+        // and https://stackoverflow.com/questions/2268065/c-sharp-language-design-explicit-interface-implementation-of-an-event
+        private NotifyCollectionChangedEventHandler _changed;
+        event NotifyCollectionChangedEventHandler INotifyCollectionChanged.CollectionChanged
+        {
+            add { _changed += value; }
+            remove { _changed -= value; }
+        }
 
         /// <summary>
         /// Clears all <see cref="CollectionChanged"/> event handlers
         /// </summary>
-        public void ClearCollectionChangedEvents() => CollectionChanged = null;
+        public void ClearCollectionChangedEvents() => _changed = null;
 
         public bool ContainsKey(TKey key)
         {