Your ROOT_URL in app.ini is https://src.whiteboxsystems.nl/ but you are visiting http://src.whiteboxsystems.nl/Whitebox/u-boot/src/commit/d4b8b5d46effb22f9735b924a7da502c2907b82b/doc/README.vf610
You should set ROOT_URL correctly, otherwise the web may not work correctly.