As part of the upcoming changes to Facebook Ads, you now must verify ownership of your domain name.
We operate a SaaS platform where user content is hosted on subdomains (myaccount.example.com etc). We need these users to be able to verify ownership of their domain so they can track their own events. We have enabled them to add the meta tag on their domain, and this verifies okay.
<meta name="facebook-domain-verification" content="codefromfbhere" />
However, the problem is, when you go into 'Events manager' -> 'Aggregated event measurement' -> 'Configure web events', it shows me the root domain instead of the subdomain I just verified (e.g. example.com instead of myaccount.example.com).
This is possible, as Leadpages has achieved the same goal. When you add in a Leadpages subdomain, you're able to verify it via meta tag, and it shows the subdomain in the 'Web event configurations' area.
I don't see any extra headers that they have provided or anything else that would enable this.
How do you mark subdomains as independent from the eTLD+1?

