Since you have upgraded your version of Sitefinity, the version of the RadControls for ASP.NET Ajax got upgraded. From looking at the screenshots it seems that the control is not able properly load its web resources. Please clear the browser cache and restart the website. Then see if there are any java script errors recorded on the pages. I have attached the default SiteTabStrip control from 3.7 SP4 version. Can you compare it to your version?
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