@Adam Terlson answer:
insertAdjacentHTML position jQuery DOM.
document.getElementById('foo').insertAdjacentHTML("beforebegin", "<hr>")
$('#foo').before("<hr>")
document.getElementById('foo').insertAdjacentHTML("afterend", "<hr>")
$('#foo').append("<hr>")
document.getElementById('foo').insertAdjacentHTML("beforeend", "<hr>")
$('#foo').append("<hr>")
document.getElementById('foo').insertAdjacentHTML("afterbegin", "<hr>")
$('#foo').prepend("<hr>")
MDN , , :
<p>
foo
</p>
@Adam Terlson , afterbegin afterend.