diff --git a/pkgs/applications/networking/browsers/firefox/common.nix b/pkgs/applications/networking/browsers/firefox/common.nix
index d335313df7b..c0822e478f3 100644
--- a/pkgs/applications/networking/browsers/firefox/common.nix
+++ b/pkgs/applications/networking/browsers/firefox/common.nix
@@ -197,7 +197,7 @@ buildStdenv.mkDerivation ({
     substituteInPlace \
       media/webrtc/trunk/webrtc/modules/desktop_capture/desktop_capture_generic_gn/moz.build \
       --replace /usr/include ${pipewire.dev}/include
-  '' + lib.optionalString (lib.versionAtLeast ffversion "80") ''
+  '' + lib.optionalString (lib.versionAtLeast ffversion "80" && lib.versionOlder ffversion "81") ''
     substituteInPlace dom/system/IOUtils.h \
       --replace '#include "nspr/prio.h"'          '#include "prio.h"'