Missing OS entry and grub after dual boot install

Hi, so I’ve installed Ubuntu alongside EndeavourOS quite a few times now (always Endeavour first, then Ubuntu) without any problems. This time, though, I installed Lubuntu after Endeavour, and now a couple of weird things have happened. I rebooted into Endeavour, and as usual I wanted to run grub-mkconfig to add Lubuntu. However, all grub-related programs (e.g. grub-mkconfig and just grub) have disappeared, except for grub-colour-chooser. arch-chroot has also disappeared, but now I have chroot.

My /boot directory is empty, except for a file called intel-ucode.img. Instead I have the directory /efi which contains my EndeavourOS entries in /efi/loader/entries. I had never noticed the directory before, and I don’t have it on my other computer that just has single-boot Endeavour.

If I chroot into the Lubuntu install I can see that it has the /boot directory, with entries for Lubuntu. It does not have an /efi directory.

It also has to be said that right now I still have the old boot menu where I can select Endeavour with LTS or normal kernel, just like before.

Why has this happened, and how can I fix it? I have not dared reinstalling any grub-related programs because I’m afraid to mess things up even more.

I have had a look at the article on systemd-boot, and the discussions here and here, but since they don’t point me to the cause of the problem, and I’m not sure they point to the right solution, I haven’t tried any of them yet.

Output of sudo parted -l:

Model: KBG30ZMV512G TOSHIBA (nvme)
Disk /dev/nvme0n1: 512GB
Sector size (logical/physical): 512B/512B
Partition Table: gpt
Disk Flags: 

Number  Start   End     Size    File system  Name         Flags
 1      2097kB  1051MB  1049MB  fat32                     boot, esp
 2      1051MB  486GB   485GB   ext4         endeavouros
 3      486GB   512GB   26,2GB  ext4         root

Output of efibootmgr:

BootCurrent: 0000
Timeout: 2 seconds
BootOrder: 0000,0001,0002
Boot0000* Linux Boot Manager	HD(1,GPT,315977f0-dda0-fb4a-88b2-6f2b558b4231,0x1000,0x1f4000)/File(\EFI\SYSTEMD\SYSTEMD-BOOTX64.EFI)
Boot0001* UEFI OS	HD(1,GPT,315977f0-dda0-fb4a-88b2-6f2b558b4231,0x1000,0x1f4000)/File(\EFI\BOOT\BOOTX64.EFI)0000424f
Boot0002* ubuntu	HD(1,GPT,315977f0-dda0-fb4a-88b2-6f2b558b4231,0x1000,0x1f4000)/File(\EFI\UBUNTU\SHIMX64.EFI)

EndeavourOS uses systemd-boot by default. That is why you are not seeing grub-specific “stuff” in your EnOS.

That being said, I’m afraid I don’t know how to add boot entries for a system which doesn’t use systemd-boot (Lubuntu) to EnOS’ boot menu.

If there is a way of doing it, I’m sure other users will chime in and help you out.