Reading FBBlob crashes when using manual transaction

[Kagu-chan]

Following Code:

const { createConnection } = require('firebird');

const isFBBlob = (obj) => {
  return (
    obj &&
    typeof obj === 'object' &&
    'isReadable' in obj &&
    'inAsyncCall' in obj
  );
};

const con = createConnection();
con.connectSync(
  '127.0.0.1/3050:testdb',
  'sysdba',
  'masterkey',
  ''
);

const query = "SELECT AMSIDNR, INFO, GRUND FROM TERMIN WHERE AMSIDNR = ?;";
const args = [
  "ITE000000225314",
]

const obj = con;
// const obj = con.startNewTransactionSync();

const result = obj.prepareSync(query);

// result.execInTransSync(obj, ...(args || []));
result.execSync(...(args || []));

const res = result.fetchSync('all', true);

function getData(rows) {
  return Promise.all(
    rows.map(async row => {
      let key;
  
      for (key in row) {
        if (row[key]) {
          const val = row[key];
  
          if (isFBBlob(val)) {
            row[key] = await new Promise((resolve, reject) => {
              val._readAll((err, bf) => {
                if (err) {
                  reject(err);
                }
  
                resolve(bf);
              });
            });
          }
        }
      }
  
      return row;
    }),
  )
}

getData(res).then((rows) => {
  obj.commitSync();
  console.log(rows);
});

This code runs through just fine. In the sample here, the field INFO is a BLOB_SUBTYPE_TEXT.
As soon as i switch the lines 25 / 26 and 30 / 31 to use a manual created transaction, the code just stops and the process dies without a word.

After some testing i can say that the code crashes as soon as FBBlob._openSync() (index.js#L105 in this repo) is called - the same when trying to use the stream class (index.js#L162).

Is there (again #115 ) a method / parameter i missed or is this a limitation at any point?