Someone who posts something random on your Facebook wall, or comments on a post for the sole purpose of being seen by someone else/making their presence known. Usually done by an ex-gf/bf, a wanna-be gf/bf or in sneaky cases, by someone who wants you to friend them but does not want to send a friend request for fear of being rejected, so posts it on mutual friend's page.
Usually this pop-up is ignored, like most screen pop-ups because it's an obvious "look at me" attempt.
Jenny: "Did you see that random post on Tom's wall from his ex?"

Alexis: "Yeah, I'm not worried. It's just a wall-stalk pop-up. He doesn't even talk to her anymore."
by jb3625 January 20, 2011
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When an urban family decides to move to the countryside and start a small farm without knowledge on farming. The local farmers call this family the urban pop up.
That ol' family that just moved to McDonald's old farm is an urban pop up.
by potatoali August 10, 2017
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