Question about writing above signatures

[Linguist_]

Every so often I see people with writing that's normally above their signature if they have one, or looks like their signature if they don't. It's normally just the name of a website - 'Google', 'YouTube', 'UC' to name the ones I see most often. It's not a link, and it doesn't seem to have any purpose. The only thing I could think is that it's where you heard about AetherCards or were linked from? Can anyone shed some light on it?

[xZEROx]

If you click "Profile", then "Forum Profile" in "Modify Profile", there are a list of things you could fill in. For example, "AetherCards Products I Own", "Facebook", "Found The Discourse via", "My Content", etc.

Some of these would show up below your avatar in your posts, some would show up the same place as your signature, and some would show up in your profile page. The "Google", "YouTube", "UC" you see would fall under "Found The Discourse via" section and show up at the signature.