Wordpress: Which mo-files are loaded?

mo-files-scan.php

/*
Plugin Name: Mo-Files
Description: Which Mo-Files are loaded?
*/
function translation_scan($mo_file,$domain) {
    global $TRANSLATION_FILES;
    $TRANSLATION_FILES .= "<tr><td>$domain</td><td>$mo_file</td></tr>";
    return $mo_file;
}
add_filter( 'load_textdomain_mofile', 'translation_scan' , 11, 2 );

function after_textdomain() {
  global $TRANSLATION_FILES;
  $TRANSLATION_FILES = "<h1>Which mo-files are loaded?</h1><table><tr><th>Domain</th><th>Mo-file</th></tr>$TRANSLATION_FILES</table>";
  if(is_home() || is_front_page())
    $TRANSLATION_FILES .= '<br/><br/>Scanned on ' . strftime('%Y-%m-%d / %H:%M:%S') . " at '" . get_the_title() . "'";
    file_put_contents(dirname(__FILE__)."/translation.html",$TRANSLATION_FILES);
}
add_action('wp_head','after_textdomain');

function translation_scan_admin_menu() {
  add_options_page('Mo-Files','Mo-Files','manage_options','translation-files','translation_files');
}
add_action("admin_menu","translation_scan_admin_menu");

function translation_files() {
  echo file_get_contents(dirname(__FILE__)."/translation.html");
}