diff --git a/engine/common.cpp b/engine/common.cpp
index f9475658be..76e7faa8e8 100644
--- a/engine/common.cpp
+++ b/engine/common.cpp
@@ -1304,7 +1304,7 @@ unsigned int COM_GetIdealDestinationCompressionBufferSize_ZSTD(
     return 4 + ZSTD_compressBound(uncompressedSize);
 }
 
-static constexpr int ZSTD_COMPRESSION_LEVEL = 22;
+static constexpr int ZSTD_COMPRESSION_LEVEL = 22; // ZSTD_btultra2
 static auto g_pZSTDCCtx                     = ZSTD_createCCtx();
 
 template<typename T>
diff --git a/zstd_game_data/css.dictionary b/zstd_game_data/css.dictionary
index 475f1919e9..e166f7eaca 100644
Binary files a/zstd_game_data/css.dictionary and b/zstd_game_data/css.dictionary differ