Comment 30 for bug 1929255

bionic:
link_in_boot = yes

# dpkg-query -W linux-base
linux-base 4.5ubuntu1.6

# Two regular flavours
# ls -latr /boot/ | grep -- '->' | sort
lrwxrwxrwx 1 root root 26 Jun 23 14:08 vmlinuz.old -> vmlinuz-4.15.0-147-generic
lrwxrwxrwx 1 root root 29 Jun 23 14:08 initrd.img.old -> initrd.img-4.15.0-147-generic
lrwxrwxrwx 1 root root 29 Jun 23 14:10 vmlinuz -> vmlinuz-4.15.0-147-lowlatency
lrwxrwxrwx 1 root root 32 Jun 23 14:10 initrd.img -> initrd.img-4.15.0-147-lowlatency

# selfbuilt
# installkernel 5.13.0-051300rc7-generic image/boot/vmlinuz-5.13.0-051300rc7-generic modules/boot/System.map-5.13.0-051300rc7-generic
run-parts: executing /etc/kernel/postinst.d/apt-auto-removal 5.13.0-051300rc7-generic /boot/vmlinuz-5.13.0-051300rc7-generic
run-parts: executing /etc/kernel/postinst.d/initramfs-tools 5.13.0-051300rc7-generic /boot/vmlinuz-5.13.0-051300rc7-generic
update-initramfs: Generating /boot/initrd.img-5.13.0-051300rc7-generic
run-parts: executing /etc/kernel/postinst.d/xx-update-initrd-links 5.13.0-051300rc7-generic /boot/vmlinuz-5.13.0-051300rc7-generic
I: /boot/initrd.img.old is now a symlink to initrd.img-4.15.0-147-lowlatency
I: /boot/initrd.img is now a symlink to initrd.img-5.13.0-051300rc7-generic
run-parts: executing /etc/kernel/postinst.d/zz-update-grub 5.13.0-051300rc7-generic /boot/vmlinuz-5.13.0-051300rc7-generic

# ls -latr /boot/ | grep -- '->' | sort
lrwxrwxrwx 1 root root 29 Jun 23 14:10 vmlinuz.old -> vmlinuz-4.15.0-147-lowlatency
lrwxrwxrwx 1 root root 32 Jun 23 14:13 vmlinuz -> vmlinuz-5.13.0-051300rc7-generic
lrwxrwxrwx 1 root root 32 Jun 23 14:14 initrd.img.old -> initrd.img-4.15.0-147-lowlatency
lrwxrwxrwx 1 root root 35 Jun 23 14:14 initrd.img -> initrd.img-5.13.0-051300rc7-generic