Trying to figure out how nostr:npub1mftv2j67vayavkks8rqev3u8jjhefe86tf80msstfxvpunk9vmps6prkl3 works ...

I had an ad open since a year or so and now somebody contacted me on it. Our "common friend" is the mailbox number. WTH? Might this and maybe other numbers be worthy of black-listing for the purpose of friend-of-a-friend estimates?

Also, as a beginner I did not understand that this was the most important information I should have looked for given my ad was limited to "friends of friends". Maybe that "common friend" should be zero clicks away, not one?