diff --git a/tests/test_framework/phpbb_functional_test_case.php b/tests/test_framework/phpbb_functional_test_case.php
index 8ab6469e9a..c600cba5f8 100644
--- a/tests/test_framework/phpbb_functional_test_case.php
+++ b/tests/test_framework/phpbb_functional_test_case.php
@@ -349,5 +349,6 @@ class phpbb_functional_test_case extends phpbb_test_case
 		$this->assertEquals(200, $this->client->getResponse()->getStatus());
 		$content = $this->client->getResponse()->getContent();
 		$this->assertNotContains('Fatal error:', $content);
+		$this->assertNotContains('[phpBB Debug]', $content);
 	}
 }