fix: window list handler

scss/vendor/_jsxc.scss

@@ -29,11 +29,11 @@
 #jsxc-roster {
   padding-top: 5px; // NC >= 14
   top: 45px;
-  z-index: 1500;
+  z-index: 1550;
 }
 
 #jsxc-window-list,
-#jsxc_windowListSB {
+#jsxc-window-list-handler {
   z-index: 1500;
 }