For what I see, using the inspector tool of google chrome the plugin can’t access to the css files stored here https://s0.wp.com/widgets.wp.com/notes/css/notes-widget.css?v=20150517
and here
https://s0.wp.com/widgets.wp.com/notes/css/notes-shared.css?v=20150517, both have error code 403 (forbidden)
