public static function enable($force_profile = null)
 {
     if ($force_profile) {
         self::$_current_profile = $force_profile;
         $force_profile::enable_custom_translations();
         $force_profile::enable_custom_code();
         return;
     }
     if (self::$_current_profile) {
         return;
     }
     if (!class_exists('Subsite')) {
         return;
     }
     if (!Subsite::currentSubsiteID()) {
         return;
     }
     $profile = Subsite::currentSubsite()->Profile;
     if (!$profile) {
         return;
     }
     self::$_current_profile = $profile;
     $profile::enable_custom_translations();
     $profile::enable_custom_code();
 }