“Your Page was flagged because your post(s) linked to domain_placeholder.com.” — an email I got last night.

Um…yeah. Sure. That’s not a valid domain name.

The message showed up less than an hour after I logged into Facebook for the first time in weeks, and it does appear to actually be from Facebook and not a phish.

But I don’t see any indication in Facebook’s website that the page in question has been flagged for anything, much less “sharing, distributing or promoting content inauthentically.” (In other words, selling links. Which I don’t do anyway.) I haven’t clicked on the tracked links just in case it is a phish, but there’s a link to submit an appeal that goes to a non-tracked Facebook Help page…which is a 404.

Searching for domain_placeholder.com on Facebook and Twitter turned up other people reacting to similar messages they got last night…and nothing older.

I’m confident it’s bogus, and I suspect it was sent out accidentally. Maybe someone at Facebook is testing a new email template, and accidentally sent it to a real subset of users on a real mail server.

Update (4/18): The Facebook Help page linked in the message now contains the following statement:

No action required

You may have received an email that we sent out in error, and your Page may not have violated the Pages Policy on restrictions around sharing, distributing or promoting content inauthentically. Please ignore the email you received on 04/15/2019.

We apologize for any inconvenience.

So it looks like it was what I expected: a test message sent out by mistake.

Update (4/19): Four days later, Facebook finally sent me a follow-up email saying, “We sent you an email by mistake.”