Merge pull request #101274 from worldofpeace/gnome-logout-button

nixos/display-managers: add sessionData.desktops to XDG_DATA_DIRS

nixos/modules/services/x11/display-managers/default.nix

@@ -474,6 +474,12 @@ in
             )
             [dms wms]
           );
+
+    # Make xsessions and wayland sessions available in XDG_DATA_DIRS
+    # as some programs have behavior that depends on them being present
+    environment.sessionVariables.XDG_DATA_DIRS = [
+      "${cfg.displayManager.sessionData.desktops}/share"
+    ];
   };
 
   imports = [