diff --git a/NEWS b/NEWS
index 92ab1f936b..54dffc58c6 100644
--- a/NEWS
+++ b/NEWS
@@ -16,6 +16,7 @@ Bug fixes
  - [web] properly encode HTML attributes in Contacts module to avoid XSS issues
  - [web] handle c_mail field format of quick record of contacts of v3 (#3443)
  - [web] fixed all-day events covering a timezone change (#3457)
+ - [web] fixed display of invitation with a category (#3590)
 
 2.3.11 (2016-05-12)
 -------------------
diff --git a/UI/WebServerResources/SchedulerUI.js b/UI/WebServerResources/SchedulerUI.js
index eb6cdcb2f2..8b067671d6 100644
--- a/UI/WebServerResources/SchedulerUI.js
+++ b/UI/WebServerResources/SchedulerUI.js
@@ -1991,7 +1991,7 @@ function newBaseEventDIV(eventRep, event, eventText) {
             categoryStyle = 'category_' + categoriesStyles.keys().length;
             categoriesStyles.set([category], categoryStyle);
         }
-        innerDiv.addClassName(categoryStyle);
+        gradientDiv.addClassName(categoryStyle);
     }
     eventCell.observe("contextmenu", onMenuCurrentView);