Invalid markup in class.yith-wcwl-ui.php

Line 61 of class.yith-wcwl-ui.php

$html .= '<img src="' . esc_url( admin_url( 'images/wpspin_light.gif' ) ) . '" class="ajax-loading" id="add-items-ajax-loading" alt="" width="16" height="16" style="visibility:hidden" />';

The id here-> id=add-items-ajax-loading
causes invalid markup to be generated on product loop page where there are more than 1 products on the page.

Can you please change this to be a class?

Thanks!

Ed

https://ww.wp.xz.cn/plugins/yith-woocommerce-wishlist/