public function setAccessKey( $accessKey ) {
		$accessKey = is_string( $accessKey ) && strlen( $accessKey ) ? $accessKey : null;

		if ( $this->accessKey !== $accessKey ) {
			if ( $accessKey !== null ) {
				$this->accessKeyed->setAttributes( [ 'accesskey' => $accessKey ] );
			} else {
				$this->accessKeyed->removeAttributes( [ 'accesskey' ] );
			}
			$this->accessKey = $accessKey;

			// Only if this is a TitledElement
			if ( method_exists( $this, 'updateTitle' ) ) {
				$this->updateTitle();
			}
		}

		return $this;
	}