When called, this middleware renders an error page. By default if an HTML response is expected it will render static error pages from the `/public` directory. For example when this middleware receives a 500 response it will render the template found in `/public/500.html`. If an internationalized locale is set, this middleware will attempt to render the template in `/public/500.<locale>.html`. If an internationalized template is not found it will fall back on `/public/500.html`.
When a request with a content type other than HTML is made, this middleware will attempt to convert error information into the appropriate response type.