diff --git a/src/Notepads/Core/NotepadsCore.cs b/src/Notepads/Core/NotepadsCore.cs
index 1c1f5744d..c94bc3d99 100644
--- a/src/Notepads/Core/NotepadsCore.cs
+++ b/src/Notepads/Core/NotepadsCore.cs
@@ -814,7 +814,7 @@ private void Sets_DragItemsCompleted(ListViewBase sender, DragItemsCompletedEven
 
         private async void Sets_SetDraggedOutside(object sender, SetDraggedOutsideEventArgs e)
         {
-            if (Sets.Items?.Count > 1 && e.Set.Content is ITextEditor textEditor)
+            if (Sets.Items?.Count > 1 && e.Set?.Content is ITextEditor textEditor)
             {
                 // Only allow untitled empty document to be dragged outside for now
                 if (!textEditor.IsModified && textEditor.EditingFile == null)