If you are dual booting Windows 10 with Ubuntu. Install Grub to EFI partition.

grub-install -V

grub-install –version

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Description:

Unzip and copy the “Aurora-Penguinis-GRUB2” folder in:

/boot/grub/themes

(create the themes folder if not exist)

add:

GRUB_DEFAULT=saved
GRUB_SAVEDEFAULT=true

GRUB_THEME=/boot/grub/themes/Aurora-Penguinis-GRUB2/theme.txt

to:

/etc/default/grub

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Finally, update grub config to take effect by command:

sudo update-grub