Your ROOT_URL in app.ini is https://src.whiteboxsystems.nl/ but you are visiting http://src.whiteboxsystems.nl/Whitebox/u-boot/blame/commit/5ec0003b19cbdf06ccd6941237cbc0d1c3468e2d/configs/pdm360ng_defconfig You should set ROOT_URL correctly, otherwise the web may not work correctly.
upstream u-boot with additional patches for our devices/boards: https://lists.denx.de/pipermail/u-boot/2017-March/282789.html (AXP crashes) ; Gbit ethernet patch for some LIME2 revisions ; with SPI flash support
u-boot/configs/pdm360ng_defconfig