FIX: [STUDIO-1563] dark mode of dataview's header

Change-Id: Ied9358df9d2edd9f0d40a81694655b8f2fdefdb8

src/slic3r/GUI/Preferences.cpp

@@ -513,6 +513,8 @@ void PreferencesDialog::set_dark_mode()
     NppDarkMode::SetDarkExplorerTheme(this->GetHWND());
     NppDarkMode::SetDarkTitleBar(this->GetHWND());
     wxGetApp().UpdateDlgDarkUI(this);
+    SetActiveWindow(wxGetApp().mainframe->GetHWND());
+    SetActiveWindow(GetHWND());
 #endif
 #endif
 }