Forum Moderators: open
Pop-up blockers block pop-ups that are not initiated by you. That means if you click a link on a page and the user has JavaScript enabled in their browser you can open a new window and retrieve another url page.
The pop up you see is probably doing something quite similar and the url it happens to be retrieving is a PHP-generated page (with a .php extension).
Something like this:
<html><head><title>Title</title></head><body>
<p><a href="mypage.php" onclick="window.open(this.href,'MyPage','height=300,width=550,menubar,resizable,scrollbars');return false;" rel="external">My Page</a></p>
</body></html>
