header – Random pop up on Firefox without toolbars

I’m getting a random pop-up in my Firefox browser, two said: Hi I’m Karol, I’m only a few feet away with her picture that popped up in the upper right hand corner of the browser

the only sites I visit are Lowe’s, My email, My bank account and a few other legit sites that are secure, I clicked on the link to see where it sent me and nothing happens

has anyone else received this message from a pop-up, how can i get rid of it.