Disabled DoubleBuffered for Tabs

+ set helper functions like a static (GUI_ObjectList.cpp)

src/slic3r/GUI/GUI_ObjectList.cpp

@@ -44,12 +44,12 @@ static PrinterTechnology printer_technology()
 }
 
 // Config from current edited printer preset
-DynamicPrintConfig& printer_config()
+static DynamicPrintConfig& printer_config()
 {
     return wxGetApp().preset_bundle->printers.get_edited_preset().config;
 }
 
-int extruders_count()
+static int extruders_count()
 {
     return printer_technology() == ptSLA ? 1 :
         printer_config().option<ConfigOptionFloats>("nozzle_diameter")->values.size();

src/slic3r/GUI/Tab.cpp

@@ -74,7 +74,7 @@ void Tab::set_type()
 void Tab::create_preset_tab()
 {
 #ifdef __WINDOWS__
-    SetDoubleBuffered(true);
+//     SetDoubleBuffered(true);
 #endif //__WINDOWS__
 
     m_preset_bundle = wxGetApp().preset_bundle;