/etc/default/grub (with a
sudo nano /etc/default/grub and change it to ...
and update grub with ...
Tell systemd to not load the desktop with ...
sudo systemctl enable multi-user.target --force
sudo systemctl set-default multi-user.target
And the initial boot will end up on a tty. By default it will be tty1. You can still go to the desktop by using the command
startx on commandline.
I should also be able to switch to the graphical desktop using ctrl +alt+f7 in case I need it.
You will need to issue the
sudo systemctl start lightdm command before using control+alt+f7. Probably impossible to get around that: if a desktop is loaded during boot it will take precedence.