get(/* _key */) {
      // always returns false for `get` because (due to the `set` just below)
      // the cached return value from the set will prevent this getter from _ever_
      // being called after a set has occurred
      return false;
    }
Accessed as a classname binding to apply the component's `disabledClass`
      CSS `class` to the element when the link is disabled.
  
      When `true`, interactions with the element will not trigger route changes.
      @property disabled
      @public