Your ROOT_URL in app.ini is https://src.whiteboxsystems.nl/ but you are visiting http://src.whiteboxsystems.nl/Whitebox/u-boot/src/commit/ffa8bcd7f1373a8e720b4c9404aa093e7780e205/doc/README.vf610
You should set ROOT_URL correctly, otherwise the web may not work correctly.