diff --git a/nixos/modules/config/xdg/portal.nix b/nixos/modules/config/xdg/portal.nix
index 3dda22eb5789..07d4fa76c2e8 100644
--- a/nixos/modules/config/xdg/portal.nix
+++ b/nixos/modules/config/xdg/portal.nix
@@ -139,7 +139,7 @@ in
         should either set `xdg.portal.config` or `xdg.portal.configPackages`
         to specify which portal backend to use for the requested interface.
 
-        https://github.com/flatpak/xdg-desktop-portal/blob/main/doc/portals-conf.rst
+        https://github.com/flatpak/xdg-desktop-portal/blob/1.18.1/doc/portals.conf.rst.in
 
         If you simply want to keep the behaviour in < 1.17, which uses the first
         portal implementation found in lexicographical order, use the following: