diff --git a/lib/behat/lib.php b/lib/behat/lib.php
index 8f6fb064b3d..2d85506ecaf 100644
--- a/lib/behat/lib.php
+++ b/lib/behat/lib.php
@@ -219,7 +219,7 @@ function behat_clean_init_config() {
         'wwwroot', 'dataroot', 'dirroot', 'admin', 'directorypermissions', 'filepermissions',
         'umaskpermissions', 'dbtype', 'dblibrary', 'dbhost', 'dbname', 'dbuser', 'dbpass', 'prefix',
         'dboptions', 'proxyhost', 'proxyport', 'proxytype', 'proxyuser', 'proxypassword',
-        'proxybypass', 'theme', 'pathtogs', 'pathtodu', 'aspellpath', 'pathtodot', 'skiplangupgrade',
+        'proxybypass', 'pathtogs', 'pathtodu', 'aspellpath', 'pathtodot', 'skiplangupgrade',
         'altcacheconfigpath', 'pathtounoconv', 'alternative_file_system_class', 'pathtopython'
     ));