I can boot with UEFI: PXE, but not with UEFI:HTTP on my x4. On my X2L both UEFI:PXE and UEFI:HTTP works fine (IPv4)
HTTP UEFI boot on X4
Ok, I managed to get it to boot if I set the boot url manually (it should support getting it from the DHCP server) - and then it only supports https.
I have verified that I can connect to PXE via DHCP, and my server is https.
PXE booting works as it should, but UEFI HTTP does not (it works in the X2L). It should be able to pick up the url from the dhcp server.