Ticket #24797: 24797.2.diff

wp-content/themes/twentythirteen/style.css

@@ -733 +733 @@
         font-weight: 300;
 }
 
+.wp-caption .wp-caption-text {
+        width: -webkit-calc(100% - 10px);
+        width:         calc(100% - 10px);
+}
+
 img.wp-smiley,
 .rsswidget img {
         border: 0;

wp-content/themes/twentytwelve/style.css

@@ -377 +377 @@
         line-height: 2;
         color: #757575;
 }
+.wp-caption .wp-caption-text {
+        width: -webkit-calc(100% - 10px);
+        width:         calc(100% - 10px);
+}
 img.wp-smiley,
 .rsswidget img {
         border: 0;