diff --git a/src/Avalonia.Diagnostics/Diagnostics/ViewModels/MainViewModel.cs b/src/Avalonia.Diagnostics/Diagnostics/ViewModels/MainViewModel.cs
index 3adad38ac6..f993d2c957 100644
--- a/src/Avalonia.Diagnostics/Diagnostics/ViewModels/MainViewModel.cs
+++ b/src/Avalonia.Diagnostics/Diagnostics/ViewModels/MainViewModel.cs
@@ -44,6 +44,7 @@ namespace Avalonia.Diagnostics.ViewModels
             SelectedTab = 0;
             if (root is TopLevel topLevel)
             {
+                _pointerOverRoot = topLevel;
                 _pointerOverSubscription = topLevel.GetObservable(TopLevel.PointerOverElementProperty)
                     .Subscribe(x => PointerOverElement = x);