Do not change the statusicon if we don't have a status icon

mitterlib/ui/ui_pygtk.py

@@ -434,6 +434,7 @@ class Interface(object):
 
         replies = self._main_tabs.get_nth_page(1)
         self._update_title(data, replies.count)
+        if self._statusicon:
             if (data + replies.count) > 0:
                 self._statusicon.set_from_pixbuf(self._images['new-messages'])
                 return
@@ -450,6 +451,7 @@ class Interface(object):
 
         messages = self._main_tabs.get_nth_page(0)
         self._update_title(messages.count, data)
+        if self._statusicon:
             if (data + messages.count) > 0:
                 self._statusicon.set_from_pixbuf(self._images['new-messages'])
                 return