Or after you boot your TW installation, you could try running (IIRC that worked too, but since I can't find any documentation for this command, the use AT YOUR OWN RISK disclaimer is in effect here :)): /sbin/update-bootloader --reinit FWIW, this command is use in the post install rpm scriptlets for the grub2-x86_64-efi package; `rpm -q --scripts grub2-x86_64-efi` to see the whole storyboard.