Your ROOT_URL in app.ini is https://source.parasitstudio.de:63000/ but you are visiting https://source.parasitstudio.de/wirtz/AutoConnect/blame/commit/6a8f7d771e8e6aea8c117d9602ce2b4e7def65ff/library.properties
You should set ROOT_URL correctly, otherwise the web may not work correctly.
paragraph=A library for easy implementing the Web interface constituting the WLAN for ESP8266 WiFi connection. With this library to make a sketch which connects from ESP8266 to the access point at runtime by the web interface without hardcoded SSID and password.