missing required attribute property

I replaced Domain Name with zzzzzzz
This is the errors we see when looking at jigsaw. Line Errors are hidden in Footer.

Error Line 377, Column 196: Element link is missing required attribute property.

<link rel='stylesheet' id='su-box-shortcodes-css'  href='http://zzzzzzz.com/wp-content/plugins/shortcodes-ultimate/assets/css/box-shortcodes.css?ver=4.7.1' type='text/css' media='all' />

Error Line 378, Column 203: Element link is missing required attribute property.

<link rel='stylesheet' id='su-content-shortcodes-css'  href='http://zzzzzzz.com/wp-content/plugins/shortcodes-ultimate/assets/css/content-shortcodes.css?ver=4.7.1' type='text/css' media='all' />

https://ww.wp.xz.cn/plugins/shortcodes-ultimate/