small fix

src/ui/view/GUI.java

@@ -394,7 +394,7 @@ public class GUI<E> implements CategoryListener {
 
 				if (tabbedPane.getMousePosition() != null) {
 					tabTemp = tabbedPane;
-				} else {
+				} else if (tabbedPane2.getMousePosition() != null) {
 					tabTemp = tabbedPane2;
 				}
 				model.getSelectedCpsObjects().clear();