When you visit someone else's domain and see your site instead, this is most likely not intentional mirroring of your site.
The most common cause of your site showing when you visit someone else's domain name is that they used to have your server's IP address and their domain's DNS is still pointing to your server's IP address.
To prevent your site from appearing on someone else's domain when they forget to change their DNS, the easiest thing to do is make a default app.
When a request comes to your server with a domain that isn't recognized by SellCloud, the app on your server whose name is alphabetically first will be shown. Creating a default app will prevent anyone from seeing your site through someone else's domain.
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