diff --git a/graf2d/doc/v600/index.md b/graf2d/doc/v600/index.md
index 0412dba3a977c5ad0471e41797dc458d73216155..011bc4ddfcff80cceb8a791eee5862259adf8471 100644
--- a/graf2d/doc/v600/index.md
+++ b/graf2d/doc/v600/index.md
@@ -83,6 +83,9 @@ file `simple.pdf`.
     Now the text appears directly as it will show and it is possible to
     enter several text string. The input is not block in the `RequestString` event loop.
 -   The toolbar methods now work without XOR mode (useful for OpenGL()).
+-   A new "vertex compression" algorithm added to deal with complex histograms
+    (thousands/millions of bins - polygons with thousands/millions of vertices) -
+    optimization/fix for X11 crashes.
 
 ### TGaxis and TAxis