This is the content of my ~/.xsession:
#!/bin/bash
# Tray for skype, keyboard layout, ...
trayer --edge top --align right --SetDockType true --SetPartialStrut true --expand true --width 10 --transparent true --tint 0x686868 --height 17 &
# Keyboard layout switcher
setxkbmap -layout us,se -option 'grp:alt_shift_toggle' &
xscreensaver -nosplash &
After login with xmonad selected in lightdm, xscreensaver is not running, neither is trayer, and setxkbmap is not setup.
I have seen this question, which is exactly the same, but the answers there did not help:
~/.xsessionis executable for all- I have no option "Custom session" in the login manager (Ubuntu's default)