- Patch #78328 by Bart: fixed incorrect Etag

includes/bootstrap.inc

@@ -414,7 +414,7 @@ function drupal_page_header() {
     if (($modified_since !== NULL || $none_match !== NULL) && $modified_since !== FALSE && $none_match !== FALSE) {
       header('HTTP/1.1 304 Not Modified');
       // All 304 responses must send an etag if the 200 response for the same object contained an etag
-      header('Etag: $etag');
+      header("Etag: $etag");
       exit();
     }