Index: wp-admin/includes/meta-boxes.php
===================================================================
--- wp-admin/includes/meta-boxes.php	(revision 24796)
+++ wp-admin/includes/meta-boxes.php	(working copy)
@@ -186,6 +186,7 @@
 	}
 ?>
 	<a class="hide-if-no-js" href="<?php echo esc_url( get_edit_post_link( $args['args']['revision_id'] ) ); ?>"><?php _ex( 'Browse', 'revisions' ); ?></a>
+	<span class="hide-if-js"><?php _e( '(Browsing requires JavaScript)' ); ?></span>
 </div>
 <?php endif;