Warning: Found multiple default providers for kernel_parameter: grub2, grub; using grub2
Error: /Stage[main]/Profiles::Grub/Kernel_parameter[elevator]: Could not evaluate: Augeas didn't load /boot/efi/EFI/fedora/grub.cfg with Shellvars_list.lns: Iterated lens matched less than it should (line:9, character:3)
on UEFI systems, grub.cfg will be located at:
/boot/efi/EFI/fedora/grub.cfg
And you'll end up with this error:
This adds the UEFI grub.cfg location as per https://docs.fedoraproject.org/en-US/Fedora/23/html/Multiboot_Guide/GRUB-configuration.html