diff --git a/pkgs/applications/networking/browsers/firefox/common.nix b/pkgs/applications/networking/browsers/firefox/common.nix
index 4a3172b6f594..1147e22241e5 100644
--- a/pkgs/applications/networking/browsers/firefox/common.nix
+++ b/pkgs/applications/networking/browsers/firefox/common.nix
@@ -248,7 +248,6 @@ buildStdenv.mkDerivation ({
     unset AS
   '' + (lib.optionalString enableOfficialBranding ''
     export MOZILLA_OFFICIAL=1
-    export BUILD_OFFICIAL=1
   '');
 
   configureFlags = [