We have automated build bash script where at the beginning executed command
apt-get update; apt-get upgrade -q -y -u --allow-downgrades --allow-remove-essential --allow-change-held-packages --allow-change-held-packages --allow-unauthenticated;
but it keeps asking this question with popup in terminal
A new version (/tmp/grub.xC3mMKP0zx) of configuration file /etc/default/grub is available, but the version installed currently has been locally modified.
which is reason that automated script execution is hanging and i can't force skip it somehow with --allow* or -y options
our ubuntu is 16.04
how i kan avoid that popup appearce ?
Please help, Thanks
-- UPDATE --
I have tried many solutions also this one: Force non-interactive "dpkg --configure" when using apt-get install which was mentioned as duplicate to this question
apt-get -o DPkg::Options::=--force-confdef upgrade -q -y -u --force-yes
it still the same promt popup asking for choose default option