diff --git a/MapUiTools/Shared/MapLayerMenuItem.cs b/MapUiTools/Shared/MapLayerMenuItem.cs
index 5f12ff2c..11e2054a 100644
--- a/MapUiTools/Shared/MapLayerMenuItem.cs
+++ b/MapUiTools/Shared/MapLayerMenuItem.cs
@@ -27,7 +27,7 @@ namespace MapControl.UiTools
 #if AVALONIA
         [Content]
 #endif
-        public FrameworkElement MapLayer { get; set; }
+        public virtual FrameworkElement MapLayer { get; set; }
 
         public Func<Task<FrameworkElement>> MapLayerFactory { get; set; }