Index: src/wp-content/themes/twentyeleven/style.css
===================================================================
--- src/wp-content/themes/twentyeleven/style.css	(revision 45458)
+++ src/wp-content/themes/twentyeleven/style.css	(working copy)
@@ -1839,6 +1839,9 @@
 .widget a:active {
 	text-decoration: underline;
 }
+.widget select {
+	max-width: 100%;
+ }
 
 /* Search Widget */
 .widget_search form {
Index: src/wp-content/themes/twentytwelve/style.css
===================================================================
--- src/wp-content/themes/twentytwelve/style.css	(revision 45458)
+++ src/wp-content/themes/twentytwelve/style.css	(working copy)
@@ -1415,6 +1415,9 @@
 /* =Widgets
 -------------------------------------------------------------- */
 
+.widget select {
+	max-width: 100%;
+ }
 .widget-area .widget ul ul {
 	margin-left: 12px;
 	margin-left: 0.857142857rem;