You did manual partitioning and deleted your EFI system partition, but you booted the installer in EFI mode. If you want to install in EFI mode, you need to put back the EFI system partition. If you want to boot in bios mode, you need to boot the installer in bios mode, and create a 1 mb bios_grub partition on GPT disks.
** Changed in: grub-installer (Ubuntu) Status: New => Invalid -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1776618 Title: grub-installer package To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/grub-installer/+bug/1776618/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs