configure( config, oldConfig ) {

		this.element.style.display = (
			config.controls &&
			(config.controls !== 'speaker-only' || this.Reveal.isSpeakerNotes())
		) ? 'block' : 'none';

		this.element.setAttribute( 'data-controls-layout', config.controlsLayout );
		this.element.setAttribute( 'data-controls-back-arrows', config.controlsBackArrows );

	}
Called when the reveal.js config is updated.