XDG_CONFIG_DIRS and LXQt

I’m trying to track down how the contents of the environment variable XDG_CONFIG_DIRS are assembled for a LXQt session (launched from Ly). (I’m experimenting on 26.05.) So far I patched the xsession script created by nixpkgs/nixos/modules/services/x11/desktop-managers/lxqt.nix to get some debug outputs and the startlxqt script that gets exec’d. The build-up the paths in XDG_CONFIG_DIRSlooks fine. But when I run cat /proc/$(pgrep -f "lxqt-session")/environ | tr '\0' '\n' | grep -a "XDG_CONFIG_D...