don't blindly and inconsistently kill scrollbars

skins/base/css/common.css

@@ -34,15 +34,6 @@ h2 {
     margin-bottom: 16px;
 }
 
-/* FIXME: show them on hoverover, and fix for firefox */
-::-webkit-scrollbar {
-    display: none;
-}
-
-html {
-    overflow: -moz-scrollbars-none;
-}
-
 .mx_ContextualMenu_background {
     position: fixed;
     top: 0;
@@ -153,4 +144,4 @@ html {
     font-weight: bold;
     font-size: 20px;
     line-height: 1.4;
-}
+}