Your ROOT_URL in app.ini is https://source.parasitstudio.de:63000/ but you are visiting https://source.parasitstudio.de/wirtz/MicroDexed/src/commit/3b8d9ea7ebae5ac467edd4bdc61934450f3aea00/addon/SD/13/piano_04.syx
You should set ROOT_URL correctly, otherwise the web may not work correctly.