diff --git a/src/Uno.UI.RuntimeTests/Tests/Windows_UI_Xaml/Given_FrameworkElement_EffectiveViewport.cs b/src/Uno.UI.RuntimeTests/Tests/Windows_UI_Xaml/Given_FrameworkElement_EffectiveViewport.cs
index 6a25c9aed445..b67f8e4287cc 100644
--- a/src/Uno.UI.RuntimeTests/Tests/Windows_UI_Xaml/Given_FrameworkElement_EffectiveViewport.cs
+++ b/src/Uno.UI.RuntimeTests/Tests/Windows_UI_Xaml/Given_FrameworkElement_EffectiveViewport.cs
@@ -1120,12 +1120,12 @@ public EVPTreeListener(FrameworkElement root, FrameworkElement leaf)
 				_root = root;
 				_leaf = leaf;
 
-				leaf.Loaded += ElementLoaded;
+				leaf.Loading += ElementLoading;
 			}
 
-			private void ElementLoaded(object sender, RoutedEventArgs e)
+			private void ElementLoading(FrameworkElement sender, object args)
 			{
-				_leaf.Loaded -= ElementLoaded;
+				_leaf.Loading -= ElementLoading;
 
 				Subscribe(sender);
 
@@ -1155,7 +1155,7 @@ public EVPListener Of<T>()
 
 			public void Dispose()
 			{
-				_leaf.Loaded -= ElementLoaded;
+				_leaf.Loading -= ElementLoading;
 				foreach (var listener in _listeners.Values)
 				{
 					listener.Dispose();
diff --git a/src/Uno.UI/UI/Xaml/FrameworkElement.EffectiveViewport.cs b/src/Uno.UI/UI/Xaml/FrameworkElement.EffectiveViewport.cs
index 7c1d3ea0abf3..3e3b05f52349 100644
--- a/src/Uno.UI/UI/Xaml/FrameworkElement.EffectiveViewport.cs
+++ b/src/Uno.UI/UI/Xaml/FrameworkElement.EffectiveViewport.cs
@@ -33,6 +33,7 @@ partial class FrameworkElement : IFrameworkElement_EffectiveViewport
 	{
 		private static readonly RoutedEventHandler ReconfigureViewportPropagationOnLoad = (snd, e) => ((_This)snd).ReconfigureViewportPropagation();
 		private event TypedEventHandler<_This, EffectiveViewportChangedEventArgs>? _effectiveViewportChanged;
+		private bool _hasNewHandler;
 		private int _childrenInterestedInViewportUpdates;
 		private IDisposable? _parentViewportUpdatesSubscription;
 		private ViewportInfo _parentViewport = ViewportInfo.Empty; // WARNING: Stored in parent's coordinates space, use GetParentViewport()
@@ -45,6 +46,7 @@ public event TypedEventHandler<_This, EffectiveViewportChangedEventArgs> Effecti
 		{
 			add
 			{
+				_hasNewHandler = true;
 				_effectiveViewportChanged += value;
 				ReconfigureViewportPropagation(isInternal: true);
 			}
@@ -321,8 +323,14 @@ private void PropagateEffectiveViewportChange(
 				+ $"| reason: {caller} "
 				+ $"| children: {_childrenInterestedInViewportUpdates}");
 
-			if (!isInternal && viewportUpdated) // We don't want to raise the event when we are only initializing the tree due to a new event handler
+			if (viewportUpdated
+				&& (
+					!isInternal // We don't want to raise the event when we are only initializing the tree due to a new event handler somewhere in sub tree
+					|| _hasNewHandler // but if we have a new local handler, we do need to raise the event!
+				))
 			{
+				_hasNewHandler = false;
+
 				// Note: The event only notify about the parentViewport (expressed in local coordinate space!),
 				//		 the "local effective viewport" is used only by our children.
 				_effectiveViewportChanged?.Invoke(this, new EffectiveViewportChangedEventArgs(parentViewport.Effective));