After using the config editor it's no longer necessary to restart mpv.net.

src/WPF/AboutWindow.xaml.cs

@@ -9,10 +9,15 @@ namespace mpvnet
         public AboutWindow()
         {
             InitializeComponent();
+            DataContext = this;
             ContentBlock.Text = App.Version;
         }
 
         protected override void OnPreviewKeyDown(KeyEventArgs e) => Close();
         protected override void OnMouseDown(MouseButtonEventArgs e) => Close();
+
+        public Theme Theme {
+            get => Theme.Current;
+        }
     }
 }