diff --git a/src/Avalonia.Input/MouseDevice.cs b/src/Avalonia.Input/MouseDevice.cs
index b9dd6c505d..4d54e44fc8 100644
--- a/src/Avalonia.Input/MouseDevice.cs
+++ b/src/Avalonia.Input/MouseDevice.cs
@@ -219,7 +219,7 @@ namespace Avalonia.Input
                 InputModifiers = inputModifiers
             };
 
-            source.RaiseEvent(e);
+            source?.RaiseEvent(e);
             return e.Handled;
         }