The error I am getting with html 5 validation is:
Line 423, Column 228: Element link is missing required attribute property.
…s-widget/assets/css/jquery.bxslider.css?ver=3.8′ type=’text/css’ media=’all’ />
Line 424, Column 201: Element link is missing required attribute property.
…dget/assets/css/testimonials-widget.css?ver=3.8′ type=’text/css’ media=’all’ />
This plugin has the only CSS link in the bottom, the rest are scripts.