Actually I think I see the problem; it isn't safe to use apt-install in a post-base-installer.d hook because that will try to do immediate installation without bind-mounting /run. A base-installer.d hook should work better here.
Actually I think I see the problem; it isn't safe to use apt-install in a post-base- installer. d hook because that will try to do immediate installation without bind-mounting /run. A base-installer.d hook should work better here.