User blog comment:Rappy 4187/Technical Update: May 4, 2015/@comment-4714517-20150506064529/@comment-452-20150507114853

While I agree that there should be the option for users to dismiss the "Best Practices" nag, here's how to hide it in your CSS: .preview-modal-msg-wrapper, .preview-modal-msg { display: none !important; }