diff --git a/components/chmhelp/packages/chm/chmreader.pas b/components/chmhelp/packages/chm/chmreader.pas
index c23269ae2e..f589f558ac 100644
--- a/components/chmhelp/packages/chm/chmreader.pas
+++ b/components/chmhelp/packages/chm/chmreader.pas
@@ -23,7 +23,7 @@ unit chmreader;
 {$mode objfpc}{$H+}
 
 //{$DEFINE CHM_DEBUG}
-{$DEFINE CHM_DEBUG_CHUNKS}
+//{$DEFINE CHM_DEBUG_CHUNKS}
 
 interface