Don't show scrollbar if not necessary

css/converse.css

@@ -2341,7 +2341,7 @@
           list-style: none; }
           #converse-embedded-chat .chatroom .box-flyout .chatroom-body .occupants ul.occupant-list,
           #conversejs .chatroom .box-flyout .chatroom-body .occupants ul.occupant-list {
-            overflow-y: scroll;
+            overflow-y: auto;
             height: -webkit-calc(100% - 205px);
             height: calc(100% - 205px); }
           #converse-embedded-chat .chatroom .box-flyout .chatroom-body .occupants ul.features-list,

sass/_chatrooms.scss

@@ -117,7 +117,7 @@
                         list-style: none;
 
                         &.occupant-list {
-                            overflow-y: scroll;
+                            overflow-y: auto;
                             @include calc(height, '100% - 205px');
                         }
                         &.features-list {