Index: wp-includes/theme.php
===================================================================
--- wp-includes/theme.php	(revision 22119)
+++ wp-includes/theme.php	(working copy)
@@ -1686,7 +1686,7 @@
 			request = true;
 <?php		endif; ?>
 
-			b[c] = b[c].replace( rcs, '' );
+			b[c] = b[c].replace( rcs, ' ' );
 			b[c] += ( window.postMessage && request ? ' ' : ' no-' ) + cs;
 		}());
 	</script>