I am afraid I don’t remember what the exact error/failure was in the case that you quoting from.
In yours the following seem to be relevant:
2022-05-30 - 22:25:29 [6]: .. Target cmd: ("grub-install", "--target=x86_64-efi", "--efi-directory=/boot/efi", "--bootloader-id=endeavouros-3584", "--force") Exit code: 1 output:
Installing for x86_64-efi platform.
grub-install: error: cannot find a device for /boot/grub (is /dev mounted?).
error: cannot find a device for /boot/grub (is /dev mounted?)
I can’t recall having seen a failure like the above.
When you tried manual partitioning did you make sure to mount ESP at /boot/efi?
I guess this might be a case for @joekamprad to look into. Or other users who know what might be behind this failure.
In the meantime, If you want to try again to install, I would suggest:
-
launch Gparted in the live session, choose the disk you want to install to from the dropdown menu at the top right.
Make sure not to choose the wrong one!! -
in the menu bar got to devices and create a new partition table: GPT
Click on apply.
This will wipe your disk hence the warning above. -
launch the installer and choose automatic installation and point the installer to the relevant disk
If it fails again, please post the url of the install log in your reply.