boot – Seems booting in rescue mode Ubuntu 20.04

From yesterday evening Ubuntu 20.04 Desktop is now booting in a “strange” mode, with icons, text and everything bigger and larger than normal (looks in rescue mode).

This is the complete output of boot-repair :

boot-repair-4ppa130                                                  
(20210605_1032)

============================== Boot Info Summary     
===============================

 => No boot loader is installed in the MBR of 
/dev/sda.
 => No boot loader is installed in the MBR of  
/dev/sdb.

sda1:        

    File system:       ext4
    Boot sector type:  -
    Boot sector info: 
    Operating System:  Ubuntu 20.04.2 LTS
    Boot files:        /boot/grub/grub.cfg 
/etc/fstab /etc/default/grub

sdb1: 
    File system:       vfat
    Boot sector type:  FAT32
    Boot sector info:  No errors found in the 
Boot Parameter Block.
    Operating System:  
    Boot files:        /efi/BOOT/bkpbootx64.efi 
/efi/BOOT/bootx64.efi 
                       /efi/BOOT/fbx64.efi 
/efi/BOOT/grubx64.efi 
                       /efi/BOOT/mmx64.efi 
/efi/ubuntu/grubx64.efi 
                       /efi/ubuntu/mmx64.efi 
/efi/ubuntu/shimx64.efi 
                       /efi/ubuntu/grub.cfg


================================ 1 OS detected    
=================================

OS#1:   The OS now in use - Ubuntu 20.04.2 LTS  
CurrentSession on sda1

============================ Architecture/Host Info     ============================

CPU architecture: 64-bit
BOOT_IMAGE of the installed session in use:
/boot/vmlinuz-5.8.0-55-generic    
root=UUID=f5046f8e-a21c-44f7-aa0c-86eb09cf922f ro 
quiet splash vt.handoff=7


===================================== UEFI  
=====================================

BIOS is EFI-compatible, and is setup in EFI-mode 
for this installed-session.
SecureBoot enabled.

efibootmgr -v
BootCurrent: 0000
Timeout: 1 seconds
BootOrder: 0000,0002,0003,0005,0001,0004,0006
Boot0000* ubuntu    HD(1,GPT,9db48a8e-4ca1-4a6d- 
b266-fb916b2b2674,0x800,0x1d1c5000)/File(EFI
ubuntushimx64.efi)
Boot0001* UEFI:CD/DVD Drive BBS(129,,0x0)

Boot0002* Hard Drive       
BBS(HD,,0x0)..GO..NO........O.S.a.m.s.u.n.g. 
.S.S.D. .8.5.0. .E.V.O.   
 .2.5.0.G.B.................>..Gd-.;.A..MQ..L.2.S.6.R
.X.N.J.0.3.1.6.6.2.6. .B. . . .  
........BO..NO........O.S.a.m.s.u.n.g. .S.S.D. 
.7.5.0. .E.V.O. 
   .2.5.0.G.B.................>..Gd-.;.A..MQ..L.3.S.S.3 
.B.N.H.0.0.5.1.9.8.5. .R. . . . ........BO

Boot0003* CD/DVD Drive  
BBS(CDROM,,0x0)..GO..NO........O.T.S.S.T.c.o.r.p. 
.C.D.D.V.D.W. 
.S.H.-.2.2.4.D.B.................>..Gd-.;.A..MQ..L.9
.R.E.3.8.6.F.D.0.5.3.0.Q.Q. . . . . . ........BO

Boot0004* UEFI:Removable Device BBS(130,,0x0)

Boot0005* UEFI OS   HD(1,GPT,9db48a8e-4ca1-4a6d-
b266-fb916b2b2674,0x800,0x1d1c5000)/File(EFI
BOOTBOOTX64.EFI)..BO

Boot0006* UEFI:Network Device   BBS(131,,0x0)

78415fb8fb9b909f8029858113f1335f   sdb1/BOOT
/bkpbootx64.efi

78415fb8fb9b909f8029858113f1335f   sdb1/BOOT   
/bootx64.efi

2895d47544fd587b26c7e29be1295c27   sdb1/BOOT
/fbx64.efi

e169c84b62cae5d67d21f3412edf807f   sdb1/BOOT
/grubx64.efi

dc3c47be2f78a78e5e57d097ae6c5c84   sdb1/BOOT
 /mmx64.efi
e169c84b62cae5d67d21f3412edf807f   sdb1/ubuntu
/grubx64.efi

dc3c47be2f78a78e5e57d097ae6c5c84   sdb1/ubuntu
/mmx64.efi

78415fb8fb9b909f8029858113f1335f   sdb1/ubuntu
/shimx64.efi


============================= Drive/Partition    
Info =============================

Disks info: 
 
sda : is-GPT,   no-BIOSboot,    has-noESP,  not-
usb,    not-mmc, has-os,    2048 sectors * 512 
bytes

sdb : is-GPT,   no-BIOSboot,    has---ESP,  not-
usb,    not-mmc, no-os, 2048 sectors * 512 bytes

Partitions info (1/3):  

sda1    : is-os,    64, apt-get,    signed grub-
pc grub-efi ,   grub2,  grub-install,   grubenv-
ok, update-grub,    farbios

sdb1    : no-os,    32, nopakmgr,   no-docgrub, 
nogrub, nogrubinstall,  no-grubenv, 
noupdategrub,   farbios

Partitions info (2/3): 

sda1    : isnotESP, fstab-has-goodEFI,  no-nt,  
 no-winload,    no-recov-nor-hid,   no-bmgr,    
notwinboot

sdb1    : is---ESP, part-has-no-fstab,  no-nt,  
no-winload, no-recov-nor-hid,   no-bmgr,    
notwinboot

Partitions info (3/3): 

sda1    : not-sepboot,  with-boot,  fstab-
without-boot,   not-sep-usr,    with--usr,  
fstab-without-usr,  std-grub.d, sda

sdb1    : not-sepboot,  no-boot,    part-has-no-
fstab,  not-sep-usr,    no---usr,   part-has-no-
fstab,  std-grub.d, sdb

fdisk -l (filtered): 

 Disk sda: 232.91 GiB, 250059350016 bytes, 
488397168 sectors
Disk identifier: 775C9C9D-
396F-4B66-9D21-89F3980F2FC1
      Start       End   Sectors   Size Type

sda1   2048 488396799 488394752 232.9G Linux 
filesystem
Disk sdb: 232.91 GiB, 250059350016 bytes, 
488397168 sectors

 Disk identifier: C13CF275-89A7-4C38-
BCE5-2378A910AFB0
      Start       End   Sectors   Size Type

sdb1   2048 488396799 488394752 232.9G EFI System

 parted -lm (filtered): 

sda:250GB:scsi:512:512:gpt:ATA Samsung SSD 850:;

1:1049kB:250GB:250GB:ext4::;
sdb:250GB:scsi:512:512:gpt:ATA Samsung SSD 750:;

1:1049kB:250GB:250GB:fat32::boot, esp;

blkid (filtered): 

NAME   FSTYPE   UUID                                 
PARTUUID                             LABEL 
PARTLABEL

sda                                                                                             
└─sda1 ext4     f5046f8e-a21c-44f7-
aa0c-86eb09cf922f ed2bda81-190b-4b82-
b4c7-49243ee64d32       

sdb                                                                                             

└─sdb1 vfat     2F90-9EC4                            
9db48a8e-4ca1-4a6d-b266-fb916b2b2674       

df (filtered): 

                   Avail Use% Mounted on
sda1              179.7G  16% /
sdb1              232.8G   0% /mnt/boot-sav/sdb1

Mount options:
sda1              rw,relatime,errors=remount-ro

sdb1                 
  rw,relatime,fmask=0022,dmask=0022,codepage=437,iochar   
set=iso8859-1,shortname=mixed,errors=remount-ro

====================== sda1/boot/grub/grub.cfg        
(filtered) ======================


Ubuntu   f5046f8e-a21c-44f7-aa0c-86eb09cf922f
Ubuntu, with Linux 5.8.0-55-generic   f5046f8e-   
a21c-44f7-aa0c-86eb09cf922f
Ubuntu, with Linux 5.8.0-53-generic   f5046f8e-  
a21c-44f7-aa0c-86eb09cf922f
### END /etc/grub.d/30_os-prober ###
UEFI Firmware Settings   uefi-firmware
### END /etc/grub.d/30_uefi-firmware ###

========================== sda1/etc/fstab 
(filtered) ===========================

# <file system> <mount point>   <type>  <options>       
<dump>  <pass>
# / was on /dev/sda1 during installation
UUID=f5046f8e-a21c-44f7-aa0c-86eb09cf922f /                   
ext4    errors=remount-ro 0       1
# /boot/efi was on /dev/sdb1 during installation

/swapfile                                 none               
swap    sw              0       0
UUID=2F90-9EC4  /boot/efi       vfat    defaults        
0       1

======================= sda1/etc/default/grub    
(filtered) =======================

GRUB_DEFAULT=0
GRUB_TIMEOUT_STYLE=hidden
GRUB_TIMEOUT=10
GRUB_DISTRIBUTOR=`lsb_release -i -s 2> /dev/null 
|| echo Debian`
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"
GRUB_CMDLINE_LINUX=""

==================== sda1: Location of files 
loaded by Grub ====================

           GiB - GB             File                                 
Fragment(s)
  72,135078430 = 77,454450688   boot/grub
/grub.cfg                             1
 103,017910004 = 110,614638592  boot/vmlinuz                                   
1
  76,635093689 = 82,286305280   boot/vmlinuz-
5.8.0-53-generic                  1
 103,017910004 = 110,614638592  boot/vmlinuz-
5.8.0-55-generic                  1
  76,635093689 = 82,286305280   boot/vmlinuz.old                               
1
 107,753547668 = 115,699490816  boot/initrd.img                                
2
  77,960407257 = 83,709349888   boot/initrd.img-
5.8.0-53-generic               2

107,753547668 = 115,699490816  boot/initrd.img-
5.8.0-55-generic               2
  77,960407257 = 83,709349888   
boot/initrd.img.old                            2

===================== sda1: ls -l /etc/grub.d/     
(filtered) ======================

-rwxr-xr-x 1 root root 17622 gen 13 15:12 
10_linux
-rwxr-xr-x 1 root root 42359 gen 13 15:12    
10_linux_zfs
-rwxr-xr-x 1 root root 12894 gen 13 15:12   
20_linux_xen
-rwxr-xr-x 1 root root 12059 gen 13 15:12 30_os-
prober
-rwxr-xr-x 1 root root  1424 gen 13 15:12 
30_uefi-firmware
-rwxr-xr-x 1 root root   214 gen 13 15:12 
40_custom
-rwxr-xr-x 1 root root   216 gen 13 15:12 
41_custom

===================== sdb1/efi/ubuntu/grub.cfg    
(filtered) ======================

search.fs_uuid f5046f8e-a21c-44f7-   
aa0c-86eb09cf922f root hd0,gpt1 
set prefix=($root)'/boot/grub'
configfile $prefix/grub.cfg


Suggested repair: 
The default repair of the Boot-Repair utility 
would reinstall the grub-efi-amd64-signed of

sda1,
using the following options:           
sdb1/boot/efi,
Additional repair would be performed: unhide-    
bootmenu-10s  use-standard-efi-file  restore-efi-    
    backups  

Final advice in case of suggested repair:

Please do not forget to make your UEFI firmware 
boot on the The OS now in use - Ubuntu 20.04.2 
LTS CurrentSession entry (sdb1/efi
/****/shim****.efi (**** will be updated in the 
final message) file) !

paste.ubuntu.com ko ()
paste.debian.net ko ()

What’s going on?
How to revert back to the “normal” mode?