FIX: crash on MacOS when system logout, not really Close mainframe

Change-Id: I0e7cc73c1b4bbc663105034e82dcd7a51998e244

src/slic3r/GUI/GUI_Utils.cpp

@@ -469,7 +469,7 @@ bool generate_image(const std::string &filename, wxImage &image, wxSize img_size
     return true;
 }
 
-std::vector<wxDialog*> dialogStack;
+std::deque<wxDialog*> dialogStack;
 
 }
 }