diff -u b/core/tests/Drupal/FunctionalJavascriptTests/Ajax/AjaxFormPageCacheTest.php b/core/tests/Drupal/FunctionalJavascriptTests/Ajax/AjaxFormPageCacheTest.php
--- b/core/tests/Drupal/FunctionalJavascriptTests/Ajax/AjaxFormPageCacheTest.php
+++ b/core/tests/Drupal/FunctionalJavascriptTests/Ajax/AjaxFormPageCacheTest.php
@@ -55,7 +55,7 @@
 
     // Wait for the DOM to update. The HtmlCommand will update
     // #ajax_selected_color to reflect the color change.
-    $green_span = $this->assertSession()->waitForElement('css', "#ajax_selected_color span:contains('green')");
+    $green_span = $this->assertSession()->waitForElement('css', "#ajax_selected_color:contains('green')");
     $this->assertNotNull($green_span, 'DOM update: The selected color SPAN is green.');
 
     // Confirm the operation of the UpdateBuildIdCommand.
@@ -67,7 +67,7 @@
     $session->getPage()->selectFieldOption('select', 'red');
 
     // Wait for the DOM to update.
-    $red_span = $this->assertSession()->waitForElement('css', "#ajax_selected_color span:contains('red')");
+    $red_span = $this->assertSession()->waitForElement('css', "#ajax_selected_color:contains('red')");
     $this->assertNotNull($red_span, 'DOM update: The selected color SPAN is red.');
 
     // Confirm the operation of the UpdateBuildIdCommand.
@@ -86,7 +86,7 @@
     $session->getPage()->selectFieldOption('select', 'green');
 
     // Wait for the DOM to update.
-    $green_span2 = $this->assertSession()->waitForElement('css', "#ajax_selected_color span:contains('green')");
+    $green_span2 = $this->assertSession()->waitForElement('css', "#ajax_selected_color:contains('green')");
     $this->assertNotNull($green_span2, 'DOM update: After reload - the selected color SPAN is green.');
 
     $build_id_from_cache_first_ajax = $this->getFormBuildId();
@@ -98,7 +98,7 @@
     $session->getPage()->selectFieldOption('select', 'red');
 
     // Wait for the DOM to update.
-    $red_span2 = $this->assertSession()->waitForElement('css', "#ajax_selected_color span:contains('red')");
+    $red_span2 = $this->assertSession()->waitForElement('css', "#ajax_selected_color:contains('red')");
     $this->assertNotNull($red_span2, 'DOM update: After reload - the selected color SPAN is red.');
 
     $build_id_from_cache_second_ajax = $this->getFormBuildId();