diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index f669a3c6033..87ec359af78 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -7240,7 +7240,7 @@ let
 
   firefoxWrapper = wrapFirefox { browser = pkgs.firefox; };
 
-  firefoxPkgs = pkgs.firefox20Pkgs;
+  firefoxPkgs = pkgs.firefox21Pkgs;
 
   firefox36Pkgs = callPackage ../applications/networking/browsers/firefox/3.6.nix {
     inherit (gnome) libIDL;