diff --git a/mozilla/webshell/tests/viewer/samples/treeTest1.css b/mozilla/webshell/tests/viewer/samples/treeTest1.css
index 945983fc327..666a0cf89e7 100644
--- a/mozilla/webshell/tests/viewer/samples/treeTest1.css
+++ b/mozilla/webshell/tests/viewer/samples/treeTest1.css
@@ -14,6 +14,7 @@ tree {
 
 treeitem {
 	display: table-row;
+    visibility: collapse; 
 }
 
 treehead {
@@ -21,10 +22,20 @@ treehead {
 }
 
 treebody {
-	display: table-row-group;
-	
+	display: table-row-group;	
 }
 
+treehead > treeitem { 
+    visibility: visible; 
+} 
+treeitem[open] > treechildren > treeitem { 
+    visibility: visible; 
+}
+treebody > treeitem { 
+    visibility: visible; 
+} 
+
+
 treecell {
 	display: table-cell;
 	color: black;
@@ -46,4 +57,6 @@ treeicon {
 
 treecell[selectedcell] {
 	background-color: lightBlue;
-}
\ No newline at end of file
+}
+
+