How to keep your Ubuntu laptop running with the lid closed

 I wanted to keep using my laptop running but use my external screens, mouse and keyboard.

To achieve this, you need to make the following changes to your /etc/systemd/logind.conf file:

Change the line

#HandleLidSwitch=suspend

to

HandleLidSwitch=ignore

then, change the line

#LidSwitchIgnoreInhibited=yes

to

LidSwitchIgnoreInhibited=no

You will then need to restart, and hey presto!