Your ROOT_URL in app.ini is https://src.whiteboxsystems.nl/ but you are visiting http://src.whiteboxsystems.nl/Whitebox/u-boot/blame/commit/f5fdc3785d4beb179d2249bf1a886f679f925774/configs/spear310_nand_defconfig
You should set ROOT_URL correctly, otherwise the web may not work correctly.