Apply commit:6737287019e7 into default branch

vispa/controller/ajax.py

@@ -228,7 +228,7 @@ class AjaxController(AbstractController):
     @cherrypy.tools.method(accept="GET")
     def getextensiondatabase(self, extensionname):
         db = cherrypy.request.db
-        return ExtensionDatabase.get_data(db, extensionname, decode_json=True) or "{}"
+        return ExtensionDatabase.get_data(db, extensionname, decode_json=True) or {}
 
     @cherrypy.expose
     @cherrypy.tools.method(accept="POST")