/etc/kernel/postinst.d
NameSizeModeActions
initramfs-tools8630755editdlrm
unattended-upgrades11630755editdlrm
update-notifier15500755editdlrm
xx-update-initrd-links8820755editdlrm
zz-shim3720755editdlrm
zz-update-grub6460755editdlrm
Edit: /etc/kernel/postinst.d/zz-shim (372B)
#!/bin/sh efi_archs="x64 aa64" # Try to update shim alternative if pointing to previous shim for efi_arch in ${efi_archs}; do test -e /usr/lib/shim/shim${efi_arch}.efi.signed.latest || continue if update-alternatives --query shim${efi_arch}.efi.signed | grep "Best: /usr/lib/shim/shim${efi_arch}.efi.signed.previous" -q; then dpkg-trigger shim-kernel-check fi done