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Looks like they have come back. It's like Google flipped a switch. We are now back on track with more featured snippets than before.

It supports to see time and time again is that someone has added some of social profile page URLs. What happens here is that whatever sites you listed are the ONLY sites that will be shown. So if you added your Facebook page, YouTube Channel page and Twitter page then only links to those pages will show up. You must make sure that if you add any URLs to this section in GA, you also include your domain and any sub-domains you may want tracked as well.

I agree with Alick, this does not matter much and I don’t think this will have any impact on rankings.