[lobsterthief]

This is a newish _Chrome_ feature (within the past 2 years) that Google rolled out. Any subdomain that looks like a domain (especially ending in a common TLD) will trigger that warning.

I learned that because, at work, I architected a system for serving certain assets for customer sites at a subdomain off a shared root domain, keyed by their full domain (like example.com.example.org—where example.com is the customer’s site domain). We ended up changing to example-com.example.org which is far better anyways since this feature started breaking stuff once it rolled out.

But this is a Chrome feature and should not affect your rankings themselves. But couldn’t hurt to take it down just in case.

[JakeSkii]

Interesting, thanks for the insight!