diff --git a/modules/core/src/main/resources/views/modules/sys/menuTree.html b/modules/core/src/main/resources/views/modules/sys/menuTree.html
index 87fea3e3..8bc22189 100644
--- a/modules/core/src/main/resources/views/modules/sys/menuTree.html
+++ b/modules/core/src/main/resources/views/modules/sys/menuTree.html
@@ -1,4 +1,4 @@
-<ul class="sidebar-menu" id="leftMenu-${parameter.parentCode}">
+<ul class="sidebar-menu first-open" id="leftMenu-${parameter.parentCode}">
 <% 
 	var p = {parentCode: parameter.parentCode};
 	menu.tree(p); print(p.html);