The old (slightly broken) behavior of the xmonad module was to put the vanilla xmonad binary into PATH. This was changed to put the users xmonad into PATH instead.
But since the config for the xmonad test uses `launch` (to avoid xmonads self-recompilation logic), it now can't handle the `--restart` flag anymore. So instead use a key binding for restarting, and let xmonad spawn a new xterm on restart.
The key binding has to be explicitly added because the default binding
will shell out to `xmonad --restart` and therefore not work with the `launch` entrypoint.
This module allows root autoLogin, so we would break that for users, but
they shouldn't be using it anyways. This gives the impression like auto
is some special display manager, when it's just lightdm and special pam
rules to allow root autoLogin. It was created for NixOS's testing
so I believe this is where it belongs.
The upstream session files display managers use have no concept of sessions being composed from
desktop manager and window manager. To be able to set upstream session files as default
session, we need a single option. Having two different ways to set default session would be confusing,
though, so we decided to deprecate the old method.
We also created separate script for each session, just like we already had a separate desktop
file for each one, and started using displayManager.sessionPackages mechanism to make the
session handling more uniform.
