But your opinion is fine, it is just a different philosophy.
]]>I advise to use this option everytime.
Not installing Recommends will lead to reduced or just plain broken functionality for most users.
IMO configuring the bootloader so that the theme is consistent with the new display manager seems sensible, and even perhaps a really nice idea. Purists wouldn't dream of installing bloat like display managers anyway.
]]>echo 'APT::Install-Recommends "0";' > /etc/apt/apt.conf.d/00norecommends
apt install lightdm
...was used (if installed via a terminal).
If so, my guess (also based on my own experience) is that the package desktop-base was also pulled in with that command, which will change the grub theme.
If you ever try again, use the command...
apt install lightdm --no-install-recommends
...in order to avoid pulling in desktop-base.
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