I needed to reinstall GRUB on my PC after updating Archlinux as instructed here https://archlinux.org/news/gru…

For me that was:

1sudo grub-install --target=x86_64-efi --efi-directory=/efi --bootloader-id=GRUB
2sudo grub-mkconfig -o /boot/grub/grub.cfg

Installing themes ¶

for example https://github.com/AllJavi/tar…

1sudo cp tartarus -r /usr/share/grub/themes/
2sudo vim /etc/default/grub
3# change GRUB_THEME= to GRUB_THEME="/usr/share/grub/themes/tartarus/theme.txt"
4sudo grub-mkconfig -o /boot/grub/grub.cfg