Inconsistency Grub Menu vs. /boot/grub/grub.cfg

[74cmonty]

Hello!
I have a question regarding the content of Grub Menu vs.
/boot/grub/grub.cfg.
In my case the content is inconsistent.
And this is causing an issue with booting a BTRFS snapshot, because the
required snapshot won't boot with the options displayed in Grub Menu.

I'm running these software packages:
Debian 9.9
grub-common = 2.02
grub-efi-amd64 = 2.02
Linux kernel = 4.15.18-14

If you check the attached screenshot, the line "linux" and "initrd" are
different compared to /boot/grub/grub.cfg:
#
# DO NOT EDIT THIS FILE
#
# It is automatically generated by grub-mkconfig using templates
# from /etc/grub.d and settings from /etc/default/grub
#

### BEGIN /etc/grub.d/00_header ###
if [ -s $prefix/grubenv ]; then
  set have_grubenv=true
  load_env
fi
if [ "${next_entry}" ] ; then
   set default="${next_entry}"
   set next_entry=
   save_env next_entry
   set boot_once=true
else
   set default="0"
fi

if [ x"${feature_menuentry_id}" = xy ]; then
  menuentry_id_option="--id"
else
  menuentry_id_option=""
fi

export menuentry_id_option

if [ "${prev_saved_entry}" ]; then
  set saved_entry="${prev_saved_entry}"
  save_env saved_entry
  set prev_saved_entry=
  save_env prev_saved_entry
  set boot_once=true
fi

function savedefault {
  if [ -z "${boot_once}" ]; then
    saved_entry="${chosen}"
    save_env saved_entry
  fi
}
function load_video {
  if [ x$feature_all_video_module = xy ]; then
    insmod all_video
  else
    insmod efi_gop
    insmod efi_uga
    insmod ieee1275_fb
    insmod vbe
    insmod vga
    insmod video_bochs
    insmod video_cirrus
  fi
}

if [ x$feature_default_font_path = xy ] ; then
   font=unicode
else
insmod part_gpt
insmod btrfs
set root='hd0,gpt3'
if [ x$feature_platform_search_hint = xy ]; then
  search --no-floppy --fs-uuid --set=root --hint-bios=hd0,gpt3
--hint-efi=hd0,gpt3 --hint-baremetal=ahci0,gpt3  9bffc581-bb88-4aa3-b8da-1a6
a1054bd0a
else
  search --no-floppy --fs-uuid --set=root
9bffc581-bb88-4aa3-b8da-1a6a1054bd0a
fi
    font="/@snapshots/36/snapshot/usr/share/grub/unicode.pf2"
fi

if loadfont $font ; then
  set gfxmode=auto
  load_video
  insmod gfxterm
  set locale_dir=$prefix/locale
  set lang=de_DE
  insmod gettext
fi
terminal_output gfxterm
if [ "${recordfail}" = 1 ] ; then
  set timeout=30
else
  if [ x$feature_timeout_style = xy ] ; then
    set timeout_style=menu
    set timeout=5
  # Fallback normal timeout code in case the timeout_style feature is
  # unavailable.
  else
    set timeout=5
  fi
fi
### END /etc/grub.d/00_header ###

### BEGIN /etc/grub.d/05_debian_theme ###
set menu_color_normal=cyan/blue
set menu_color_highlight=white/blue
### END /etc/grub.d/05_debian_theme ###

### BEGIN /etc/grub.d/10_linux ###
function gfxmode {
        set gfxpayload="${1}"
}
set linux_gfx_mode=
export linux_gfx_mode
menuentry 'Proxmox Virtual Environment GNU/Linux' --class proxmox
--class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-s
imple-9bffc581-bb88-4aa3-b8da-1a6a1054bd0a' {
        load_video
        insmod gzio
        if [ x$grub_platform = xxen ]; then insmod xzio; insmod lzopio; fi
        insmod part_gpt
        insmod btrfs
        set root='hd0,gpt3'
        if [ x$feature_platform_search_hint = xy ]; then
          search --no-floppy --fs-uuid --set=root --hint-bios=hd0,gpt3
--hint-efi=hd0,gpt3 --hint-baremetal=ahci0,gpt3  9bffc581-bb88-4aa3-
b8da-1a6a1054bd0a
        else
          search --no-floppy --fs-uuid --set=root
9bffc581-bb88-4aa3-b8da-1a6a1054bd0a
        fi
        echo    'Linux 4.15.18-14-pve wird geladen …'
        linux   /@snapshots/36/snapshot/boot/vmlinuz-4.15.18-14-pve
root=UUID=9bffc581-bb88-4aa3-b8da-1a6a1054bd0a ro
        echo    'Initiale Ramdisk wird geladen …'
        initrd  /@snapshots/36/snapshot/boot/initrd.img-4.15.18-14-pve
}
submenu 'Erweiterte Optionen für Proxmox Virtual Environment GNU/Linux'
$menuentry_id_option 'gnulinux-advanced-9bffc581-bb88-4aa3-b8da-1a6
a1054bd0a' {
        menuentry 'Proxmox Virtual Environment GNU/Linux, mit Linux
4.15.18-14-pve' --class proxmox --class gnu-linux --class gnu --class o
s $menuentry_id_option
'gnulinux-4.15.18-14-pve-advanced-9bffc581-bb88-4aa3-b8da-1a6a1054bd0a' {
                load_video
                insmod gzio
                if [ x$grub_platform = xxen ]; then insmod xzio; insmod
lzopio; fi
                insmod part_gpt
                insmod btrfs
                set root='hd0,gpt3'
                if [ x$feature_platform_search_hint = xy ]; then
                  search --no-floppy --fs-uuid --set=root
--hint-bios=hd0,gpt3 --hint-efi=hd0,gpt3 --hint-baremetal=ahci0,gpt3 
9bffc581-bb
88-4aa3-b8da-1a6a1054bd0a
                else
                  search --no-floppy --fs-uuid --set=root
9bffc581-bb88-4aa3-b8da-1a6a1054bd0a
                fi
                echo    'Linux 4.15.18-14-pve wird geladen …'
                linux  
/@snapshots/36/snapshot/boot/vmlinuz-4.15.18-14-pve
root=UUID=9bffc581-bb88-4aa3-b8da-1a6a1054bd0a ro
                echo    'Initiale Ramdisk wird geladen …'
                initrd 
/@snapshots/36/snapshot/boot/initrd.img-4.15.18-14-pve
        }
}

### END /etc/grub.d/10_linux ###

### BEGIN /etc/grub.d/20_linux_xen ###

### END /etc/grub.d/20_linux_xen ###

### BEGIN /etc/grub.d/30_os-prober ###
### END /etc/grub.d/30_os-prober ###

### BEGIN /etc/grub.d/30_uefi-firmware ###
menuentry 'System setup' $menuentry_id_option 'uefi-firmware' {
        fwsetup
}
### END /etc/grub.d/30_uefi-firmware ###

### BEGIN /etc/grub.d/40_custom ###
# This file provides an easy way to add custom menu entries.  Simply
type the
# menu entries you want to add after this comment.  Be careful not to change
# the 'exec tail' line above.
### END /etc/grub.d/40_custom ###

### BEGIN /etc/grub.d/41_custom ###
if [ -f  ${config_directory}/custom.cfg ]; then
  source ${config_directory}/custom.cfg
elif [ -z "${config_directory}" -a -f  $prefix/custom.cfg ]; then
  source $prefix/custom.cfg;
fi
### END /etc/grub.d/41_custom ###

### BEGIN /etc/grub.d/41_snapshots-btrfs ###
submenu 'Debian Snapshots' {
        configfile "/@snapshots/36/snapshot/boot/grub/grub-btrfs.cfg"
}
### END /etc/grub.d/41_snapshots-btrfs ###


Can you please share some information on this inconsistency and advice
how to fix it?

THX

2019-05-21_17-16-41.jpg
Description: JPEG image