Your ROOT_URL in app.ini is https://src.whiteboxsystems.nl/ but you are visiting http://src.whiteboxsystems.nl/Whitebox/u-boot/src/commit/9642b78cdf3404ada759ccb7c7de461bf25597cb/configs/TQM5200_B_defconfig
You should set ROOT_URL correctly, otherwise the web may not work correctly.