So I installed the recent 2024-01-02 stable update. Since Manjaro has upgraded from grub to grub2 I see multiple recommendations to run grub-install in the forum. But here’s the problem: I don’t how to run grub-install and I don’t want to risk breaking anything without getting some guidance first. I also have LUKS encryption and I don’t know if this will cause issues or not.
I’m not sure which logs or information to post so please tell me if needed. I installed Manjaro on December 18, 2021 with LUKS encryption (not sure if LUKS2, it’s whatever was default when I installed). I’m booting from UEFI and Secure Boot is disabled. I’m running the second latest LTS kernel (6.1.69-1). I also made some changes to /etc/default/grub at one point to improve security. Here is the output:
# GRUB boot loader configuration
GRUB_DEFAULT=saved
GRUB_TIMEOUT=1
GRUB_DISTRIBUTOR="Manjaro"
GRUB_CMDLINE_LINUX_DEFAULT="cryptdevice=UUID=[redacted] root=/dev/mapper/luks-[redacted] splash apparmor=1 security=apparmor udev.log_priority=3 slab_nomerge init_on_alloc=1 init_on_free=1 page_alloc.shuffle=1 pti=on randomize_kstack_offset=on vsyscall=none debugfs=off module.sig_enforce=1 lockdown=confidentiality quiet loglevel=0 random.trust_cpu=off intel_iommu=on efi=disable_early_pci_dma"
GRUB_CMDLINE_LINUX=""
# Preload both GPT and MBR modules so that they are not missed
GRUB_PRELOAD_MODULES="part_gpt part_msdos"
# Uncomment to enable booting from LUKS encrypted devices
GRUB_ENABLE_CRYPTODISK=y
# Set to 'countdown' or 'menu' to change timeout behavior,
# press ESC key to display menu.
GRUB_TIMEOUT_STYLE=hidden
# Uncomment to use basic console
GRUB_TERMINAL_INPUT=console
# Uncomment to disable graphical terminal
#GRUB_TERMINAL_OUTPUT=console
# The resolution used on graphical terminal
# note that you can use only modes which your graphic card supports via VBE
# you can see them in real GRUB with the command 'videoinfo'
GRUB_GFXMODE=auto
# Uncomment to allow the kernel use the same resolution used by grub
GRUB_GFXPAYLOAD_LINUX=keep
# Uncomment if you want GRUB to pass to the Linux kernel the old parameter
# format "root=/dev/xxx" instead of "root=/dev/disk/by-uuid/xxx"
#GRUB_DISABLE_LINUX_UUID=true
# Uncomment to disable generation of recovery mode menu entries
GRUB_DISABLE_RECOVERY=true
# Uncomment and set to the desired menu colors. Used by normal and wallpaper
# modes only. Entries specified as foreground/background.
GRUB_COLOR_NORMAL="light-gray/black"
GRUB_COLOR_HIGHLIGHT="green/black"
# Uncomment one of them for the gfx desired, a image background or a gfxtheme
#GRUB_BACKGROUND="/usr/share/grub/background.png"
GRUB_THEME="/usr/share/grub/themes/manjaro/theme.txt"
# Uncomment to get a beep at GRUB start
#GRUB_INIT_TUNE="480 440 1"
# Uncomment to make GRUB remember the last selection. This requires
# setting 'GRUB_DEFAULT=saved' above.
GRUB_SAVEDEFAULT=true
# Uncomment to disable submenus in boot menu
#GRUB_DISABLE_SUBMENU=y
# Uncomment this option to enable os-prober execution in the grub-mkconfig command
GRUB_DISABLE_OS_PROBER=false
# Uncomment to ensure that the root filesystem is mounted read-only so that
# systemd-fsck can run the check automatically. We use 'fsck' by default, which
# needs 'rw' as boot parameter, to avoid delay in boot-time. 'fsck' needs to be
# removed from 'mkinitcpio.conf' to make 'systemd-fsck' work.
# See also Arch-Wiki: https://wiki.archlinux.org/index.php/Fsck#Boot_time_checking
#GRUB_ROOT_FS_RO=true
I want to know two things. Firstly, can someone guide me through grub-install? I find the information quite confusing surrounding it and don’t want to mess up my system by any chance. Secondly, is it really necessary? I ask this because I want to know if future updates could break something due to an older grub.
Thank you so much to anyone who helps! 
