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/21b07971f4c2cf005b35cc05a41f6a292e25bcba/docs/bootstrap/css
You should set ROOT_URL correctly, otherwise the web may not work correctly.
Chip Audette