My system76 laptop got the grub updates this morning, and I installed (suspiciously) after running a meeting first.  Yup, the system did not boot, giving a grub prompt.  I booted with a refind USB stick, and then rolled back the grub-efi stuff to the previous version using synaptic.  That worked.
That laptop does *not* have the grub-efi-amd64-signed version installed, just the unsigned.
FYI
--Tim

    On Saturday, March 6, 2021, 1:27:12 PM EST, fsmithred via Dng <dng@???> wrote:  

On 3/4/21 11:08 PM, wirelessduck--- via Dng wrote:
>
>
>> On 5 Mar 2021, at 03:23, viverna <viverna@???> wrote:
>>
>> Yesterday I updated one of my computers with apt-get upgrade. This packages are upgraded:
>>
>> grub-common grub-pc grub-pc-bin grub2-common
>>
>> dpkg install from version 2.02+dfsg1-20+deb10u3 to version 2.02+dfsg1-20+deb10u4
>>

>>
>> And now the question. Has anyone reported the error in Devuan? Has anyone haved this problem?
>
> Seems to be a bit of news about the latest update.
> https://9to5linux.com/patches-for-multiple-new-grub2-security-flaws-start-rolling-out-to-linux-distros-update-now
>
> The changelog mentions changes to secure boot. Could that be related to the issue?
>
> https://metadata.ftp-master.debian.org/changelogs//main/g/grub2/grub2_2.02+dfsg1-20+deb10u4_changelog
>
>

I've been able to reproduce the problem in two systems that boot uefi,
(one beowulf, one chimaera) but only after I installed
grub-efi-amd64-signed. It's not necessary to have secure boot enabled; you
just need the signed package. I've been avoiding that package for over a
year because it has caused this problem in the past. If you don't need
secure boot, just use grub-efi-amd64.

I could not reproduce the problem on a system that boots legacy bios and
uses grub-pc.

fsmithred
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