function concatBuffers(buffer1, buffer2) {
  const result = new Uint8Array(buffer1.byteLength + buffer2.byteLength)
  result.set(new Uint8Array(buffer1), 0)
  result.set(new Uint8Array(buffer2), buffer1.byteLength)
  return result.buffer
}
Concatenate two buffers
@param {Uint8Array} buffer1 - first buffer
@param {Uint8Array} buffer2 - second buffer
@returns