The feature is currently available for a subset of email templates (10) and is in the beta stage. We plan to expand the capability of using a new email designer editor across all transactional email templates:
Classes of available documents actually: ORDER_CONFIRMATION,LETTER,ORDER_ACKNOWLEDGEMENT,ORDER_REJECTED,PASSWORD_CHANGE,PASSWORD_RESET,RESET_OPERATOR_PASSWORD,NEW_ACCOUNT,AUTHORIZATION_CONFIRMATION,B2B_ACCOUNT
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