As the disabled content attribute[1] applies to more than just form controls, namely the fieldset, option and optgroup elements the definition of both :enabled and :disabled[2] should be changed to match that.
At the moment this definition mainly talks about form controls and fieldset elements. Neither the option element or optgroup element is mentioned. [1]<http://whatwg.org/specs/web-forms/current-work/#disabled> [2]<http://whatwg.org/specs/web-forms/current-work/#relation> -- Anne van Kesteren <http://annevankesteren.nl/>