Re: grub crashes and restarts after an update

[Pascal Hambourg]

On 03/02/2024 at 20:09, Ishai Asa wrote:
> I'm using the Debian testing distribution. Few days ago a new grub version
> was pushed and I installed it, all seemed well as per usual updates.

The Debian GRUB version is heavily patched, so it may be worth filing a 
bug in the Debian bug tracking system.

> During the update it asked whether to keep overwriting a few grub scripts.

Did you choose to keep the existing files or replace with the new ones ?

> Maybe that has to do with grub customizer gui?

I must warn agains grub-customizer, I have seen it ruin GRUB config 
beyond repair several times.

> After the restart the grub bootloader menu shows for a fraction of a second
> and restarts.
> I'm able to boot to windows through the BIOS boot chooser.
> I tried using a boot repair disk , but it did not help.

I also warn against automated boot repair tools, you never know what 
they really do and can make things worse.

Does GRUB boot in legacy BIOS or EFI mode ?

If you can see GRUB menu, the culprit may be related with the boot config.
Launch any live system, rename /boot/grub.grub.cfg and reboot. You 
should see GRUB version and prompt. Which version is it ?
Relaunch the live system, recreate /boot/grub/grub.cfg with only a 
section of the original grub.cfg, reboot and if it works add another 
section and so on until you find the section which causes the reboot.