diff --git a/.gitignore b/.gitignore
index c757210654..06f50e9c4e 100644
--- a/.gitignore
+++ b/.gitignore
@@ -4,9 +4,7 @@
 /phpBB/cache/*.php
 /phpBB/cache/*.lock
 /phpBB/composer.phar
-/phpBB/config.php
-/phpBB/config_dev.php
-/phpBB/config_test.php
+/phpBB/config*.php
 /phpBB/ext/*
 /phpBB/files/*
 /phpBB/images/avatars/gallery/*
@@ -14,5 +12,5 @@
 /phpBB/store/*
 /phpBB/vendor
 /tests/phpbb_unit_tests.sqlite2
-/tests/test_config.php
+/tests/test_config*.php
 /tests/tmp/*
diff --git a/phpBB/install/install_install.php b/phpBB/install/install_install.php
index 78f3f00eda..cb63c70e11 100644
--- a/phpBB/install/install_install.php
+++ b/phpBB/install/install_install.php
@@ -273,8 +273,8 @@ class install_install extends module
 			$checks = array(
 				array('func_overload', '&', MB_OVERLOAD_MAIL|MB_OVERLOAD_STRING),
 				array('encoding_translation', '!=', 0),
-				array('http_input', '!=', 'pass'),
-				array('http_output', '!=', 'pass')
+				array('http_input', '!=', array('pass', '')),
+				array('http_output', '!=', array('pass', ''))
 			);
 
 			foreach ($checks as $mb_checks)
@@ -295,7 +295,8 @@ class install_install extends module
 					break;
 
 					case '!=':
-						if ($ini_val != $mb_checks[2])
+						if (!is_array($mb_checks[2]) && $ini_val != $mb_checks[2] ||
+							is_array($mb_checks[2]) && !in_array($ini_val, $mb_checks[2]))
 						{
 							$result = '<strong style="color:red">' . $lang['NO'] . '</strong>';
 							$passed['mbstring'] = false;