Adding a custom field to BACS account fields without overriding core files
问题 I have this situation - I made a changes in one of the woocommerce email templates, but I`m sure - these changes will be lost after next woocommerce update. As I know, I should use theme functions to bypass this problem. This is the code before changes: echo '<ul class="wc-bacs-bank-details order_details bacs_details">' . PHP_EOL; // BACS account fields shown on the thanks page and in emails $account_fields = apply_filters( 'woocommerce_bacs_account_fields', array( 'account_number'=> array(