--- a/libervia/server/server.py	Tue Sep 18 21:16:51 2018 +0200
+++ b/libervia/server/server.py	Tue Sep 18 21:16:53 2018 +0200
@@ -1753,12 +1753,15 @@
         return os.path.join(u'/', C.TPL_RESOURCE, template_data.site or u'sat',
             C.TEMPLATE_TPL_DIR, template_data.theme, relative_url)
 
-    def _moveFirstLevelToDict(self, options, key):
+    def _moveFirstLevelToDict(self, options, key, keys_to_keep):
         """Read a config option and put value at first level into u'' dict
 
         This is useful to put values for Libervia official site directly in dictionary,
         and to use site_name as keys when external sites are used.
         options will be modified in place
+        @param options(dict): options to modify
+        @param key(unicode): setting key to modify
+        @param keys_to_keep(list(unicode)): keys allowed in first level
         """
         try:
             conf = options[key]
@@ -1767,27 +1770,30 @@
         if not isinstance(conf, dict):
             options[key] = {u'': conf}
             return
-        default_dict = conf.setdefault(u'', {})
+        default_dict = conf.get(u'', {})
         to_delete = []
         for key, value in conf.iteritems():
-            # "/" can't be present in host name, and help to differenciate from
-            # non vhost dict (which may be used in redirections)
-            if not isinstance(value, dict) or u'/' in key:
+            if key not in keys_to_keep:
                 default_dict[key] = value
                 to_delete.append(key)
         for key in to_delete:
             del conf[key]
+        if default_dict:
+            conf[u''] = default_dict
 
     def backendReady(self, __):
         self.media_dir = self.bridge.getConfig("", "media_dir")
         self.local_dir = self.bridge.getConfig("", "local_dir")
         self.cache_root_dir = os.path.join(self.local_dir, C.CACHE_DIR)
+        self.renderer = template.Renderer(self, self._front_url_filter)
+        sites_names = self.renderer.sites_paths.keys()
 
-        self._moveFirstLevelToDict(self.options, "url_redirections_dict")
-        self._moveFirstLevelToDict(self.options, "menu_json")
+        self._moveFirstLevelToDict(self.options, "url_redirections_dict", sites_names)
+        self._moveFirstLevelToDict(self.options, "menu_json", sites_names)
+        if not u'' in self.options["menu_json"]:
+            self.options["menu_json"][u''] = C.DEFAULT_MENU
 
         # we create virtual hosts and import Libervia pages into them
-        self.renderer = template.Renderer(self, self._front_url_filter)
         self.vhost_root = vhost.NameVirtualHost()
         default_site_path = os.path.dirname(libervia.__file__)
         # self.sat_root is official Libervia site

--- a/twisted/plugins/libervia_server.py	Tue Sep 18 21:16:51 2018 +0200
+++ b/twisted/plugins/libervia_server.py	Tue Sep 18 21:16:53 2018 +0200
@@ -160,7 +160,7 @@
     ["empty_password_allowed_warning_dangerous_list", None, "", None],
     ["vhosts_dict", None, {}, None],
     ["url_redirections_dict", None, {}, None],
-    ["menu_json", None, C.DEFAULT_MENU, None],
+    ["menu_json", None, {u'': C.DEFAULT_MENU}, None],
     ["tickets_trackers_json", None, None, None],
     ["mr_handlers_json", None, None, None],
 ]