More infomation. I can not reproduce with grubnetaa64.efi from focal.
This is the focal grub I download, which can not reproduce
http://ports.ubuntu.com/ubuntu-ports/dists/focal/main/uefi/grub2-arm64/current/grubnetaa64.efi.signed
This is the groovy grub, which is able to reproduce
http://ports.ubuntu.com/ubuntu-ports/dists/groovy/main/uefi/grub2-arm64/current/grubnetaa64.efi.signed
More infomation. I can not reproduce with grubnetaa64.efi from focal.
This is the focal grub I download, which can not reproduce
http:// ports.ubuntu. com/ubuntu- ports/dists/ focal/main/ uefi/grub2- arm64/current/ grubnetaa64. efi.signed
This is the groovy grub, which is able to reproduce
http:// ports.ubuntu. com/ubuntu- ports/dists/ groovy/ main/uefi/ grub2-arm64/ current/ grubnetaa64. efi.signed