I am not overriding email extras so it is using the base one. Below is sample from that file
define('SEND_EXTRA_CREATE_ACCOUNT_EMAILS_TO_SUBJECT','[CREATE ACCOUNT]');
define('SEND_EXTRA_GV_CUSTOMER_EMAILS_TO_SUBJECT','[GV CUSTOMER SENT]');
define('SEND_EXTRA_NEW_ORDERS_EMAILS_TO_SUBJECT','[NEW ORDER]');
define('SEND_EXTRA_CC_EMAILS_TO_SUBJECT','[EXTRA CC ORDER info] #');
1) English only
2) FILENAME_EMAILS_EXTRA not found in my english.php
3)
Code:
/home/sites/25a.co.uk/public_html/includes/classes/order.php
Line #1047 : zen_mail('', SEND_EXTRA_ORDER_EMAILS_TO, SEND_EXTRA_NEW_ORDERS_EMAILS_TO_SUBJECT . ' ' . EMAIL_TEXT_SUBJECT . EMAIL_ORDER_NUMBER_SUBJECT . $zf_insert_id,
/home/sites/25a.co.uk/public_html/includes/languages/english/email_extras.php
Line #42 : define('SEND_EXTRA_NEW_ORDERS_EMAILS_TO_SUBJECT','[NEW ORDER]');