Just wondering, why has the grub2-common package two update-grub files?
https://packages.debian.org/stretch/amd64/grub2-common/filelist
File list of package grub2-common in stretch of architecture amd64
/usr/sbin/grub-install
/usr/sbin/grub-reboot
/usr/sbin/grub-set-default
/usr/sbin/update-grub
/usr/sbin/update-grub2
/usr/share/bug/grub2-common/presubj
/usr/share/bug/grub2-common/script
/usr/share/doc/grub2-common
/usr/share/grub/default/grub
/usr/share/grub/default/grub.md5sum
/usr/share/info/grub-dev.info.gz
/usr/share/info/grub.info.gz
/usr/share/man/man8/grub-install.8.gz
/usr/share/man/man8/grub-reboot.8.gz
/usr/share/man/man8/grub-set-default.8.gz
/usr/share/man/man8/update-grub.8.gz
/usr/share/man/man8/update-grub2.8.gz
One is just a symlink to the other
ls -asl update-grub*
4 -rwxr-xr-x 1 root root 64 jun 23 12:35 update-grub
0 lrwxrwxrwx 1 root root 11 jun 23 14:47 update-grub2 -> update-grub
If there are programs depending on update-grub2, a small transition might
have been a nicer solution.
Floris