This directory contains the Grub 2.0 boot records that are used by Rufus * Because of issue #2233, boot.img and core.img were created from the GRUB git source (@e67a551a48192a04ab705fca832d82f850162b64) obtained on 2023.04.25 from: https://git.savannah.gnu.org/cgit/grub.git/tree/?id=e67a551a48192a04ab705fca832d82f850162b64 on a Debian 11.6 x64 system using the commands: ./autogen.sh # --enable-boot-time for Manjaro Linux ./configure --disable-nls --enable-boot-time make -j4 cd grub-core ../grub-mkimage -v -O i386-pc -d. -p\(hd0,msdos1\)/boot/grub biosdisk fat exfat ext2 ntfs ntfscomp part_msdos -o core.img * boot.img has been modified to nop the jump @ 0x66 as per grub2's setup.c comments: /* If DEST_DRIVE is a hard disk, enable the workaround, which is for buggy BIOSes which don't pass boot drive correctly. Instead, they pass 0x00 or 0x01 even when booted from 0x80. */ * Note that, for convenience reasons, the content of boot.img is *not* the one that Rufus processes when writing the MBR. Instead, the byte array from src/ms-sys/inc/mbr_grub2.h (whose content is identical) is what Rufus uses. If you modify these files, be mindful that you may also need to update the array in mbr_grub2.h. * For details, see src/format.c, src/msys/br.c and src/msys/inc/mbr_grub2.h.