When in the need to remove certain CSS files from your application.css’s
# application.css /* *= require_self *= require_tree . */
Use sprocket’s stub
# application.css /* *= require_self *= require_tree . *= stub whatevercssyoudontwanttoload[.css] */
Note: Best practice of course is to add individual stylesheets into your application.css
rather than a full on require_tree .. But in the event that you require to
still use require_tree, the above may help you.