buster preseed autoinstall - possible bug or feature ?

[tim taler <robur314@gmail.com>]

Hi all,

I experience a strange behaviour of the debian buster installer.

I want to do a preseeded installation of a minimalistic buster system
with only one partition (no swap even).

What ever I try, if I don't configure:
"d-i partman-auto/choose_recipe select multi!
in the preseed file
tasksel is completely ignored and d-i will install 1370
packages, including the desktop (and libre-office :-)) ...

I tried all combinations of partition and tasksel with the same result:

d-i partman-auto/choose_recipe select multi   --> minimal installation
as desired
d-i partman-auto/choose_recipe select (atomic|home)   --> desktop install
d-i partman-auto/expert_recipe string (any configuration with and
without swap, same config as "multi" from above) --> desktop install

Haven't found anything about that yet on the net?
Can somebody confirm?

My setup is a manual installed minimalistic buster with apache2
serving the preseed file
and a second instance trying to do the auto install by:
>From the boot menu choose: "Advanced options" --> "Automated install"
and than providing the preseed location.

see me puzzled,
any hint is welcome!

tia