Your ROOT_URL in app.ini is https://source.parasitstudio.de:63000/ but you are visiting https://source.parasitstudio.de/wirtz/OpenAudio_ArduinoLibrary/src/commit/deace67137ffb2e46f70a4b4d3ec0405dfebf649/docs/bootstrap You should set ROOT_URL correctly, otherwise the web may not work correctly.