Fix LT-22129: Crash when clicking the Insert Affix Template (#352)

Author: jtmaxwell3

Src/xWorks/FwXWindow.cs

@@ -315,17 +315,8 @@ private void BasicInit(FwApp app)
 				m_propertyTable.SetProperty("App", app, true);
 				m_propertyTable.SetPropertyPersistence("App", false);
 			}
-			this.Deactivate += FwXWindow_Deactivate;
 		}
 
-		private void FwXWindow_Deactivate(object args, EventArgs e)
-		{
-			// The window has lost the focus.
-			// Save changes so that other applications can access them.
-			Cache.ServiceLocator.GetInstance<IUndoStackManager>().Save();
-		}
-
-
 		/// ------------------------------------------------------------------------------------
 		/// <summary>
 		/// C'tor for TESTING with MockFwXWindow