diff --git a/src/includes/classes.php b/src/includes/classes.php
index 7e3bde0..e31afe3 100644
--- a/src/includes/classes.php
+++ b/src/includes/classes.php
@@ -86,7 +86,7 @@ interface MTTHttpApiExtender
 interface MTTExtensionSettingsInterface
 {
     function settingsPage(): string;
-    function saveSettings(array $array, ?string &$userError): bool;
+    function saveSettings(array $array, ?string &$outMesssage): bool;
 }
 
 
diff --git a/src/init.php b/src/init.php
index de2f534..05c3b06 100644
--- a/src/init.php
+++ b/src/init.php
@@ -58,7 +58,7 @@ if (need_auth() && !isset($dontStartSession)) {
     setup_and_start_session();
 }
 
-if (defined('MTT_ENABLE_EXT') && MTT_ENABLE_EXT) {
+if (!defined('MTT_DISABLE_EXT')) {
     define('MTT_EXT', MTTPATH . 'ext/');
     loadExtensions();
 }
diff --git a/src/settings.php b/src/settings.php
index 47bb6ce..b0fd853 100644
--- a/src/settings.php
+++ b/src/settings.php
@@ -24,7 +24,7 @@ if(isset($_POST['save']))
     Config::set('lang', _post('lang'));
 
     // in Demo mode we can set only language by cookies
-    if (defined('MTTDEMO')) {
+    if (defined('MTT_DEMO')) {
         setcookie('lang', Config::get('lang'), 0, url_dir(Config::get('url')=='' ? getRequestUri() : Config::getUrl('url')));
         $t['saved'] = 1;
         jsonExit($t);
@@ -63,7 +63,7 @@ else if (isset($_POST['activate']))
     $t = array('saved'=>0);
 
     // in Demo mode we do nothing
-    if (defined('MTTDEMO')) {
+    if (defined('MTT_DEMO')) {
         $t['saved'] = 1;
         jsonExit($t);
     }
@@ -354,7 +354,7 @@ header('Content-type:text/html; charset=utf-8');
 </div>
 
 <?php
-    if (defined('MTT_ENABLE_EXT') && MTT_ENABLE_EXT) {
+    if (!defined('MTT_DISABLE_EXT')) {
 ?>
 <div class="tr">
  <div class="th"><?php _e('set_extensions');?>:</div>