Hi, I was trying to do a popup with the subscription form you give, but I want to do that when it submits the form it close the window and I try many things and I could not do it :( .
<div class="newsletter newsletter-subscription">
<form method="post" action="http://blabla.com.es/wp-content/plugins/newsletter/do/subscribe.php" onsubmit="return newsletter_check(this)">
I try: onsubmit="return newsletter_check(this); window.close();"
And still not working, thanks!