Index: wp-includes/css/media-views.css
===================================================================
--- wp-includes/css/media-views.css	(revision 23049)
+++ wp-includes/css/media-views.css	(working copy)
@@ -132,6 +132,7 @@
 	right: 0;
 	bottom: 0;
 	overflow: auto;
+	min-height: 300px;
 	background: #fff;
 }