I noticed my friend's Blogger subdomain site is linked to a site with .xyz domain. Is it a spam site? I checked this .xyz domain with Whois.com, and it shows it is with Namecheap, registered Jan. 2020, Registrant State/Province: Panama. What should my friend do? Can he block this domain to his Blogger site?
No, it goes to the Blogger site, but with .xyz domain. Now, there are two domains that direct to the Blogger blog.
I wonder if it came with the theme your friend downloaded. Search Google for redirect virus blogger or redirect hack blogger
I've checked with Sucuri website, it has no problems. Another thing I notice is it doesn't show and Adsense ads.