In gdm3 package, there is a /etc/gdm3/Xsession script, and in sddm
package, there's a /etc/sddm/Xsession script too. I didn't look for
other DMs though.
Maybe those scripts could be good place to add code such as:
xrdb -merge << EOF
*.newLoginCommand: /usr/bin/gdmflexiserver
EOF
... and replacing with the appropriate command for the DM we're
editing. The right script would be run by its DM, then xscreensaver is
started in the user session, with the right newLoginCommand resource.
Am I missing something?
