Your ROOT_URL in app.ini is https://source.parasitstudio.de:63000/ but you are visiting https://source.parasitstudio.de/wirtz/MicroDexed/src/commit/9c625fa238a0bed46930445cce02583f0d64a194/third-party/ArduinoJson/extras/tests/IntegrationTests You should set ROOT_URL correctly, otherwise the web may not work correctly.