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/9a7c5ef645aeb6244bcb3ec5df1a3f173190f7e1/examples/TestConvolutinalFilter
You should set ROOT_URL correctly, otherwise the web may not work correctly.