Fatal error: Uncaught Error: Call to undefined function mb_convert_encoding() in /var/www/html/include/emogrifier.class.php:434 Stack trace: #0 /var/www/html/include/emogrifier.class.php(411): Emogrifier->getUnifiedHtml() #1 /var/www/html/include/emogrifier.class.php(233): Emogrifier->createXmlDocument() #2 /var/www/html/include/functions_mail.inc.php(963): Emogrifier->emogrify() #3 /var/www/html/include/functions_mail.inc.php(861): move_css_to_body('<!DOCTYPE html ...') #4 /var/www/html/include/functions_mail.inc.php(473): pwg_mail(Array, Array, Array) #5 /var/www/html/admin/include/updates.class.php(221): pwg_mail_admins(Array, Array, false, true) #6 /var/www/html/include/page_tail.php(63): updates->notify_piwigo_new_versions() #7 /var/www/html/index.php(375): include('/var/www/html/i...') #8 {main} thrown in /var/www/html/include/emogrifier.class.php on line 434