How can I create a different session for lightdm, with different env vars?

Hey folks!

I want to have a different xsession in my lightdm greeter that is basically the same as one that is already existing, but I want to have a monitor turned off. The idea is for me to differentiate when my laptop is open and can be used as a second screen, or when it is closed and I can’t use it as a screen.

I have two DE I like to use, cinnamon and DWM. And this setup would only be needed for the DWM session. I already have a help script that sets everything up for a single screen, and I’m trying to find a way to set it up so that I can run that script.

The way I was thinking was to have a few env vars that are different per session, and I want to be able to define those. From my research, the different desktop sessions are defined in the /usr/share/xsessions through the *.desktop cfg files. How can I find more documentation on those?