docs: function toUnusableRecordBFK(recordState) {
    // if (!hasUnusableRecordIdentifier(recordState)) {
    //   return undefined;
    // }
    const md5s = recordState.md5s;
    return [
      trimOrEmpty(recordState.eventID), trimOrEmpty(recordState.eventSeqNo), trimOrEmpty(recordState.eventSubSeqNo),
      trimOrEmpty(md5s && md5s.userRec), trimOrEmpty(md5s && md5s.rec), trimOrEmpty(md5s && md5s.data)
    ].join('|');
  }