diff --git a/core/modules/media_library/tests/src/FunctionalJavascript/EntityReferenceWidgetTest.php b/core/modules/media_library/tests/src/FunctionalJavascript/EntityReferenceWidgetTest.php
index 53400620ec..ef4c45a78f 100644
--- a/core/modules/media_library/tests/src/FunctionalJavascript/EntityReferenceWidgetTest.php
+++ b/core/modules/media_library/tests/src/FunctionalJavascript/EntityReferenceWidgetTest.php
@@ -2,6 +2,7 @@
 
 namespace Drupal\Tests\media_library\FunctionalJavascript;
 
+use Drupal\Core\Database\Database;
 use Drupal\field\Entity\FieldConfig;
 
 /**
@@ -14,7 +15,7 @@ class EntityReferenceWidgetTest extends MediaLibraryTestBase {
   /**
    * {@inheritdoc}
    */
-  protected static $modules = ['field_ui'];
+  protected static $modules = ['field_ui', 'dblog'];
 
   /**
    * Test media items.
@@ -140,7 +141,20 @@ public function testWidget() {
     $this->assertTrue($menu->hasLink('Type Three'));
     $this->assertTrue($menu->hasLink('Type Four'));
     $this->assertTrue($menu->hasLink('Type Five'));
-    $assert_session->elementExists('css', '.ui-dialog-titlebar-close')->click();
+
+    // Insert media to test validation with null target_bundles.
+    $this->switchToMediaType('One');
+    $this->assertNotEmpty($assert_session->waitForText('Showing Type One media.'));
+    $this->selectMediaItem(0);
+    $this->pressInsertSelected('Added one media item.');
+    $assert_session->assertWaitOnAjaxRequest();
+    $php_error = (bool) Database::getConnection()->select('watchdog')
+      ->condition('type', 'php')
+      ->countQuery()
+      ->execute()
+      ->fetchField();
+    // Assert there was not a php warning during ajax validation.
+    $this->assertFalse($php_error);
 
     // Assert that the media type menu is not available when only 1 type is
     // configured for the field.