A lot of people are asking if "four.intern.facebook" is being used by scammers or cybercriminals. The URL four.intern.facebook is not a valid domain name. It is possible that the URL is missing the ".com" part which will make it "four.intern.facebook.com".
The "four.intern.facebook.com" goes to Facebook's legitimate website located at www.facebook.com. In other words, if you go to four.intern.facebook.com in your web browser, you will be redirected to www.facebook.com.
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