Your ROOT_URL in app.ini is https://src.whiteboxsystems.nl/ but you are visiting http://src.whiteboxsystems.nl/Whitebox/u-boot/blame/commit/3a22808f76502b0f953fb749a34b1b7d9bc3e4da/configs/imx6q_icore_nand_defconfig
You should set ROOT_URL correctly, otherwise the web may not work correctly.