我想在WordPress中显示RSS帖子。默认的RSS插件允许通过添加源来查看项目。我添加了valid RSS source，但WordPress提供了以下错误，
RSS Error: A feed could not be found at https://medium.com/feed/@mbertulli. A feed with an invalid mime type may fall victim to this error, or SimplePie was unable to auto-discover it.. Use force_feed() if you are certain this URL is a real feed.