Someone who I spoke very briefly to on Plenty Of Fish has come up in my Facebook friend suggestions. How is that possible?

Did you put their number in your phone? WhatsApp gets them and being owned by meta it links people via numbers to Facebook. Happens to me a lot

If you or they have the number still in the contacts they will still pop up. Or vice versa .

I think if you searched up their profile or vice versa, that initiates the people you may know suggestions

Did she have your real name? 😳 or did you add her phone number to your phone?

If they looked at your profile on Facebook that would do it.

Algorithms, Facebook knows everything, lolz😄
乂^◡^乂

Probably Facebook or google algorithm