You can embed custom Web pages written in [**JSON**](https://www.json.org/index.html) into AutoConnect without declaring AutoConnectAux & AutoConnectElements in sketches. Custom Web page declaration in JSON can be included in the sketch in advance as the fixed string, or it can be stored in the external file such as SPIFFS for stream loading. You can also load and save AutoConnectElements objects individually.[^1]
To process the AutoConnectAux & AutoConnectElements written in the JSON is you need to install the [ArduinoJson version 5](https://arduinojson.org/v5/doc/installation/) library.