Your ROOT_URL in app.ini is https://source.parasitstudio.de:63000/ but you are visiting https://source.parasitstudio.de/wirtz/MicroDexed/src/commit/6f08b3046a88659071a911809e7a6153fd0887b7/doc/images/MicroDexed_Panel/Transparent%20images/Horizontal%20Arrows/Horizontal%20arrow%20Blue%20both.png
You should set ROOT_URL correctly, otherwise the web may not work correctly.