Re: UEFI multiboot control usurped with each kernel update

[John Little]

On debian-based distros, I thought I had the answer to this.  debian
has a patch to the grub2-common package  (applied to grub2-2.02.02 in
my Ubuntu 18.04) called

add-an-auto-nvram-option-to-grub-install.patch

giving grub-install the "--no-nvram" option, and a debconf
configuration name grub2/update_nvram

So,

sudo dpkg-reconfigure grub-efi-amd64

gives a text dialogue that asks:

    GRUB can configure your platform's NVRAM variables so that it boots into
    Debian automatically when powered on. However, you may prefer to disable
    this behavior and avoid changes to your boot configuration. For example,
    if your NVRAM variables have been set up such that your system contacts
    a PXE server on every boot, this would preserve that behavior.

    Update NVRAM variables to automatically boot into Debian?

Seems to directly address the issue.  I answered No, then ran sudo
update-grub, which updated the nvram anyway, trampling my grub set up;
at the end of the output was

    Adding boot menu entry for EFI firmware configuration

What did I do wrong?

I was previously good, because the ubiquity installer has a
--no-bootloader (or -b) option that I used at installation.
update-grub previously did not change the EFI variables.  by running
dpkg-reconfigure grub-efi-amd64 I've now got the OP's problem.

Regards, John Little