Your ROOT_URL in app.ini is https://src.whiteboxsystems.nl/ but you are visiting http://src.whiteboxsystems.nl/Whitebox/u-boot/src/commit/8cf2f3602e6778b207f3a95fda6be3fc420a8162/board/rockchip/tinker_rk3288/Makefile
You should set ROOT_URL correctly, otherwise the web may not work correctly.