diff --git a/src/slic3r/GUI/GUI_ObjectList.cpp b/src/slic3r/GUI/GUI_ObjectList.cpp
index 69c3e3f1b..8c9f4cc4a 100644
--- a/src/slic3r/GUI/GUI_ObjectList.cpp
+++ b/src/slic3r/GUI/GUI_ObjectList.cpp
@@ -1886,8 +1886,7 @@ void ObjectList::part_selection_changed()
 
         if (item) {
             wxGetApp().obj_manipul()->get_og()->set_value("object_name", m_objects_model->GetName(item));
-            const wxString tooltip = get_mesh_errors_list(obj_idx, volume_id);
-            wxGetApp().obj_manipul()->update_warning_icon_state(tooltip);
+            wxGetApp().obj_manipul()->update_warning_icon_state(get_mesh_errors_list(obj_idx, volume_id));
         }
     }
 
diff --git a/src/slic3r/GUI/GUI_ObjectManipulation.hpp b/src/slic3r/GUI/GUI_ObjectManipulation.hpp
index da9e67d4e..5aa69cd15 100644
--- a/src/slic3r/GUI/GUI_ObjectManipulation.hpp
+++ b/src/slic3r/GUI/GUI_ObjectManipulation.hpp
@@ -2,6 +2,7 @@
 #define slic3r_GUI_ObjectManipulation_hpp_
 
 #include <memory>
+#include <wx/string.h>
 
 #include "GUI_ObjectSettings.hpp"
 #include "GLCanvas3D.hpp"
@@ -9,7 +10,6 @@
 class wxStaticText;
 class LockButton;
 class wxStaticBitmap;
-class wxString;
 
 namespace Slic3r {
 namespace GUI {