Thanks a lot @manuel.
This is the best news I heard since the start of this issue!
So, we are back to normal? (or something might change and cause an issue again?)
Sorry for asking too much… but it was painful for someone seeking a rolling release (so not to reinstall newer release) to reinstall because of such issue! (I knew latter that there was a way to recover without reinstalling, sorry… non techie here)
We don’t know what the future holds at this point. We have to wait and see. There are still ongoing discussion amongst the grub devs on if backwards compatibility is important or if grub-install should be run with grub-updates.
Keep in mind, there is no urgency on the part of the grub team around this because this isn’t code they have released. It might be some time before have answers here. There is also the possibility that clarity never comes at all.
At this point, we just need to be patient.
Thanks a lot @dalto
So, I will just be careful and do the 3 commands as before… just to be on the safe side.
Thank you very much for all what you are doing. 
I found another way without chroot. Make a bootable drive with supergrub2
and then boot the pendrive into supergrub2. Then check for available OS’s in the detect menu. Now you will be shown a list of OS’s in your PC and select your OS. Now fix your grub by updating it from inside.
grub-mkconfig -o /boot/grub/grub.cfg
grub-install --target=x86_64-efi --efi-directory=/boot/efi --bootloader-id=EndeavourOS
The steps outlined by @Lugh at comment section 620 helped me.
I had to do few additional steps with the help of @dalto. Thought I share below for others if they have a similar issue.
After the above fix, my system shows GRUB screen and takes me to computer BIOS directly.
I then chroot back and installed both Linux 5.19 and LTS kernels and ran sudo mkinitcpio -P and rebooted and I could now see boot entries. Found this at Reddit Thread
However, my UUID was incorrect so got maintenance error which was then fixed with fstab edits. Thread Link
No I meant from the original file update that caused the problem. So this file looks the same to me. Not sure what’s different about it?
/etc/grub.d/30_uefi-firmware
It is different. The if statement changed and critically, that call to fwsetup --is-supported was added.
please, I have followed this instructions and get this error
https://discovery.endeavouros.com/system-rescue/arch-chroot-for-efi-uefi-systems/2021/03/
When I do mount, there is no directory
sudo mount /dev/sda1 /mnt/EFI/boot
not
/mnt/boot/efi
and when I do arch-chroot, I got error message again
chroot: failed to run command ‘/bin/bash’: No such file or directory
please help me, I open this forum from live usb 
I have frustrated
thanks in advance.
That is clearly wrong.
Can you share lsblk -o name,type,fstype,label,size and also share all the commands you are running and the exact output?
well so It takes multiple tries to boot now and there are 3 uefis on the same disk now and not even sure which one is correct lol. The one that is the first boot option in my bios seems to be the one that works but if I don’t manually select it it somehow doesn’t use it most the time. I don’t really know how to fix this all I did was run grub install a few times and the mk config thing till I got it to work without error lol
Try deleting the old entries using efibootmgr
some muloc grub errors have to set order in bios probably too
so to be clear its basically 3 separate grubs does this tool deal with that?
It lists all the uefi entries and lets you modify them. So…yes.
so in this example would I run efibootmgr -b C -B or which entries should be removed c has the name of the one that when manually selected drops to recovery 0008 is the current one that I have to manual select despite being first boot option which I thing would be efibootmgr -b 8 -B if I wanted to delete (which obviously I don’t)
sorry for the questions I haven’t dealt with many boot loader issues like this and don’t wanna break anything lol or maybe c is the one that does the non themed boot menu that doesnt work and 6 does the recovery lol
I think this is why its borked I feel like there should not be 2 other folders and I think the highlighted one on the right one but not sure
endeavouros is made by sudo grub-install , the other two can be removed ?
you did before the fix i believe… but did grub-install again, does it has the bootorder ?
otherwise select in bios that… and remove other two.
I thought this was there originally when the problem started. This was in the file when i fist looked at it when the problem first happened.
fwsetup --is-supported
I don’t know what’s different with the if statement as i don’t have each file to compare. I’m trying to understand the file because of the way it affected the UEFI firmware on my MSI hardware. I was able to get it to boot when the problem happened. That was easy but it didn’t rectify other issues such as out of memory and lagging at the UEFI screen booting at the MSI logo. Now everything works back the way it always was. I’m just trying to understand what they changed in that file.