# Pastebin LriGK6iP
#!/bin/sh
# This script is designed to behave like 10_linux
#
# These variables represent the two volumes we're going to peek at:
ROOTFS_UUID=348e0ebd-25f4-47ab-9637-29be2520e637
BOOTFS_UUID=ade2a118-7198-4876-8e5b-12a069d2aa41

# Our prober:
grub_probe=/usr/sbin/grub-probe

# Our workspace:
ROOT_VOL=/root/mnt
mkdir -p $ROOT_VOL
mount /dev/disk/by-uuid/$ROOTFS_UUID $ROOT_VOL
mount /dev/disk/by-uuid/$BOOTFS_UUID $ROOT_VOL/boot

# Gather information
GRUB_DISTRIBUTOR=$(cat $ROOT_VOL/etc/system-release)
GRUB_DEVICE="`${grub_probe} --target=device $ROOT_VOL`"
GRUB_DEVICE_UUID="`${grub_probe} --device ${GRUB_DEVICE} --target=fs_uuid 2> /dev/null`" || true
GRUB_DEVICE_BOOT="`${grub_probe} --target=device $ROOT_VOL/boot`"
GRUB_DEVICE_BOOT_UUID="`${grub_probe} --device ${GRUB_DEVICE_BOOT} --target=fs_uuid 2> /dev/null`" || true
GRUB_FS="`${grub_probe} --target=fs $ROOT_VOL 2> /dev/null || echo unknown`"

export GRUB_DEVICE GRUB_DEVICE_UUID GRUB_DEVICE_BOOT GRUB_DEVICE_BOOT_UUID GRUB_FS GRUB_DISTRIBUTOR

# We need a slightly customized' version of /etc/grub.d/10_linux:
ROOT_VOL_10_LINUX=/root/10_linux.x
perl -pn -e 'next unless m!list=.*vmlinu!;s! /! '$ROOT_VOL'/!g' < /etc/grub.d/10_linux > $ROOT_VOL_10_LINUX
chmod +x $ROOT_VOL_10_LINUX

# Run 10_linux to get our pretty menu items
$ROOT_VOL_10_LINUX

# Clean up
rm -f $ROOT_VOL_10_LINUX
umount $ROOT_VOL/boot
umount $ROOT_VOL