diff --git a/HISTORY.md b/HISTORY.md
index 0efd932a..22d5b3cc 100644
--- a/HISTORY.md
+++ b/HISTORY.md
@@ -14,6 +14,7 @@ http://visjs.org
         .vis.timeline .item.range .content {
           overflow: visible;
         }
+- Fixed the height of background and foreground panels of groups.
 
 ### Graph