Incorrect warning when blog on subdomain

I’m preparing a blog on “blog.biblische-reisen.de”, so the “From” eMail is naturally something like “[email protected]”. But for that I get the warning:

“Warning: “Email From” is not set to an address from the same domain name as your web site (blog.biblische-reisen.de). This can sometimes cause mail not to send, or send but be delivered to a Spam folder. Be sure to test that your form is sending email and that you are receiving it, if not, fix this setting.”

Would it be possible to recode the test to omit subdomains?

Thanks, Tim

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