diff --git a/addons/im_chat/static/src/css/im_chat.css b/addons/im_chat/static/src/css/im_chat.css
index 6f76ceae193..ea350377dba 100644
--- a/addons/im_chat/static/src/css/im_chat.css
+++ b/addons/im_chat/static/src/css/im_chat.css
@@ -4,6 +4,7 @@
     background-color: #E8EBEF;
     width: 220px;
     border-left: 1px solid #AEB9BD;
+    z-index: 500;
 }
 
 @media print {