I didn"t respond when I added class to Link. I think the encapsulated component activeClassName is string,. Somehow it just doesn"t work
<Link to={{pathname:"/printPage"}} activeClassName="dddfff" target="_blank"></Link>
...
propTypes: {
    to: oneOfType([string, object, func]),
    query: object,
    hash: string,
    state: object,
    activeStyle: object,
    activeClassName: string,
    onlyActiveOnIndex: bool.isRequired,
    onClick: func,
    target: string
  },
						