diff --git a/home/modules/firefox/mkFirefoxModuleCompat.nix b/home/modules/firefox/mkFirefoxModuleCompat.nix
index dabeac4..e3cf8ea 100644
--- a/home/modules/firefox/mkFirefoxModuleCompat.nix
+++ b/home/modules/firefox/mkFirefoxModuleCompat.nix
@@ -61,7 +61,7 @@ in
     { }
     // lib.setAttrByPath modulePath {
       # Tor & Mullvad Browser don't support profile version 2 yet
-      profileVersion = null;
+      profileVersion = lib.mkDefault null;
     }
   );
 }