It happens in some users when they open a lookup from a modal screen shows what the lookup below the screen, the same applies when a message appears:

modal screen opened as follows:

 Dim MV
        Set MV = Application.MainViews.Add ("Personal:CallMainView", 2, TRUE)
        MV.CurrentID = ExisteLlamadaParaCampanya (application.BasicFunctions.CurrentAccountID, "", Application.BasicFunctions.CurrentUserID)
        MV.Show