LVM password not prompted when booting on custom kernel

I have a full disc encrypted system with an unencrypted boot folder. I did perform some tweaks during install since I have WIndows installed side-by-side, but it’s been a long time and unsure just what I did back then.

Now, my system still works perfect. If I want to change kernels, I might install an AUR kernel (e.g. Linux-LTS or Arch-hardened) and all goes well. And I can easily reboot and launch into them.

However, I need to run Anbox-git AUR package for a project and it requires me to build a custom kernel. For creating the kernel I followed the Arch-wiki on that. I furthermore applied the changes advised on the Arch wiki for Anbox. The kernel build succeeds without a problem.

Also, the new custom kernel shows up nicely in my grub menu.

However, when I boot into it, I do not get my usual password prompt. The system tries to start but fails since it cannot find device /dev/mapper/vg-root and then it drops into a root shell.

I have no idea on how to trouble shoot. I think it shouldn’t really be that hard to solve, but Googling didn’t save me here.

Anyone has any ideas on where I should look to find a solution / or how to troubleshoot this?

Thanks in advance!

Manjaro do not support systems running foreign kernels.