Comment 39 for bug 2048473

@Koen Roggemans (koen-roggemans).
You mean install a lang+kb? Gnome-initial-setup should install the lang and KB choosen by end user. Just like ubiquity does.
I have postinstall scripts to install more layouts and langs, but gnome-initial-setup does not show them.
I can only install two kb layouts with autoinstall.yaml:
tried:
no succes
packages:
    - language-pack-gnome-fr
    - language-pack-gnome-nl
    - language-pack-gnome-de
no success
    - curtin in-target -- apt-get -y install `check-language-support -l fr`
    - curtin in-target -- apt-get -y install `check-language-support -l en`
    - curtin in-target -- apt-get -y install language-pack-gnome-en
    - curtin in-target -- apt-get -y install language-pack-gnome-fr

success , but max two layouts
keyboard:
    layout: "fr,us"