diff --git a/pkgs/applications/networking/browsers/palemoon/default.nix b/pkgs/applications/networking/browsers/palemoon/default.nix
index f359f05c18ba..e4325267e600 100644
--- a/pkgs/applications/networking/browsers/palemoon/default.nix
+++ b/pkgs/applications/networking/browsers/palemoon/default.nix
@@ -115,7 +115,7 @@ stdenv.mkDerivation rec {
 
     # Too many cores can lead to build flakiness
     # https://forum.palemoon.org/viewtopic.php?f=5&t=28480
-    export jobs=$(($NIX_BUILD_CORES<=32 ? $NIX_BUILD_CORES : 32))
+    export jobs=$(($NIX_BUILD_CORES<=20 ? $NIX_BUILD_CORES : 20))
     if [ -z "$enableParallelBuilding" ]; then
       jobs=1
     fi