if ignore_layout is specified, do not change skin at all.

otherwise the result is unpredictable.

product/ERP5/Document/WebSite.py

@@ -110,6 +110,7 @@ class WebSiteTraversalHook(Persistent):
     self._v_request = request
     request.physicalPathToVirtualPath = self._physicalPathToVirtualPath
 
+    if not request.get('ignore_layout', None):
       # If a skin selection is defined in this web site, change the skin now.
       skin_selection_name = container.getSkinSelectionName()
       if skin_selection_name and request.get('portal_skin', None) is None: