Disable suspend when the laptop lid is closed:

sudo sed -i 's/#HandleLidSwitch=suspend/HandleLidSwitch=ignore/g' /etc/systemd/logind.conf
sudo sed -i 's/#HandleLidSwitchExternalPower=suspend/HandleLidSwitchExternalPower=ignore/g' /etc/systemd/logind.conf
sudo systemctl restart systemd-logind

If you are in a TTY, you can blank the screen before closing the lid to prevent burn-in. After running this, come back later and press a key to turn the screen on again.

alias blankscreen='setterm --blank=force; read ans; setterm --blank=poke'