.../src/Functional/EntityResource/EntityResourceTestBase.php   | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/core/modules/rest/tests/src/Functional/EntityResource/EntityResourceTestBase.php b/core/modules/rest/tests/src/Functional/EntityResource/EntityResourceTestBase.php
index a9130c5..eac468f 100644
--- a/core/modules/rest/tests/src/Functional/EntityResource/EntityResourceTestBase.php
+++ b/core/modules/rest/tests/src/Functional/EntityResource/EntityResourceTestBase.php
@@ -525,11 +525,11 @@ public function testGet() {
     $get_headers = $response->getHeaders();
 
     // Verify that the GET and HEAD responses are the same. The only difference
-    // is that there's no body. For this reason the 'Transfer-Encoding' header
-    // is also added to the list of headers to ignore, as this could be added to
-    // GET requests - depending on web server configuration. This would usually
-    // be 'Transfer-Encoding: chunked'.
-    $ignored_headers = ['Date', 'Content-Length', 'X-Drupal-Cache', 'X-Drupal-Dynamic-Cache', 'Transfer-Encoding'];
+    // is that there's no body. For this reason the 'Transfer-Encoding' and
+    // 'Vary' headers are also added to the list of headers to ignore, as they
+    // may be to GET requests - depending on web server configuration. They are
+    // usually 'Transfer-Encoding: chunked' and 'Vary: Accept-Encoding'.
+    $ignored_headers = ['Date', 'Content-Length', 'X-Drupal-Cache', 'X-Drupal-Dynamic-Cache', 'Transfer-Encoding', 'Vary'];
     foreach ($ignored_headers as $ignored_header) {
       unset($head_headers[$ignored_header]);
       unset($get_headers[$ignored_header]);