Your ROOT_URL in app.ini is https://src.whiteboxsystems.nl/ but you are visiting http://src.whiteboxsystems.nl/Whitebox/u-boot/blame/commit/a1dbe57d2d45d311e402c357831bbf5c5157a32c/configs/arcangel4-be_defconfig
You should set ROOT_URL correctly, otherwise the web may not work correctly.