--- /dev/null
+<?php
+
+namespace Drupal\Tests\metatag\Functional;
+
+use Drupal\Tests\BrowserTestBase;
+
+/**
+ * Verify that enabling Devel don't cause the site to blow up.
+ *
+ * @group metatag
+ */
+class EnsureDevelWorks extends BrowserTestBase {
+
+ // Contains helper methods.
+ use MetatagHelperTrait;
+
+ /**
+ * {@inheritdoc}
+ */
+ public static $modules = [
+ // Modules for core functionality.
+ 'node',
+ 'field',
+ 'field_ui',
+ 'user',
+
+ // Contrib dependencies.
+ 'token',
+
+ // This module.
+ 'metatag',
+
+ // Use the custom route to verify the site works.
+ 'metatag_test_custom_route',
+
+ // The modules to test.
+ 'devel',
+ ];
+
+ /**
+ * Load the custom route, make sure something is output.
+ */
+ public function testCustomRoute() {
+ $this->drupalGet('metatag_test_custom_route');
+ $this->assertResponse(200);
+ $this->assertText('Hello world!');
+ }
+
+ /**
+ * Make sure that the system still works when some example content exists.
+ */
+ public function testNode() {
+ $node = $this->createContentTypeNode();
+ $this->drupalGet($node->toUrl());
+ $this->assertResponse(200);
+ }
+
+}