Hello, and welcome to the forum! Sorry it is for a problem you are having with Silverblue. The BLS changed the layout a bit for grub. If you look in /boot/loader/entries/ you’ll find .conf files which are actually your menu entries for the grub menu you see at boot. These files are named ostree-1-fedora-workstation.conf, and ostree-2-fedora-workstation.conf normally. If you don’t have any there you would get no entry. Here is the results of cat on one of mine
My initrd is here
initrd /ostree/fedora-workstation-5b43ecdd038eb5389d7c2967f9d90f0e1f496c07a63de4e8bc642548c016bda1/initramfs-5.0.0-300.fc30.x86_64.img
and my kernel is here
linux /ostree/fedora-workstation-5b43ecdd038eb5389d7c2967f9d90f0e1f496c07a63de4e8bc642548c016bda1/vmlinuz-5.0.0-300.fc30.x86_64
You can see that
rpm-ostree uses the directory /ostree/fedora-worstation-ID as the name of where it stores these files for that particular commit. I’ll do some digging into possible commands to use to fix entries, I think grubby has something.
[Edit]: Just poking around my /boot I notice the initrd image for my old F29SB is sitting there.