"Press This" hook

I would like to add meta boxes to the “Press This” page (press-this.php).

I looked at press-this.php and the only hooks/do_actions I could find were:

do_action(‘admin_print_styles’);
do_action(‘admin_print_scripts’);
do_action(‘admin_head’);
do_action(‘admin_print_footer_scripts’);

I know that I can do some “AJAX,” check to see if URL is “press-this.php,” and add meta boxes with JavaScript, but that seems a very messy way to go about it.