LightDM launches different session than default session

When I start up my computer into NixOS, and log in from the greeter (lightdm-mini-greeter), nothing happens. At first I thought that my password got changed or messed up somehow, but I was able to log into a tty. After looking at the logs, it seems the session somehow got loaded as ‘xterm+xmonad’ (I used xmonad a while ago), even though my current defaultSession is ‘none+i3’. I’m running on nixos-unstable and also using home-manager.
Here are the relevant (I hope) files:

Any ideas as to why?

Have you checked the session selector of your greeter if it perhaps points to the wrong session?

Also check if you have perhaps a ~/.xsession which might overwrite anything…

Did you manage to resolve this? I’m having kind of the same issue where lightdm-mini-greeter is trying to launch a ‘default’ session but there is none. lightdm-gtk-greeter does launch the correct none+bspwm session though.