diff --git a/htdocs/application/config/ace_languages.php b/htdocs/application/config/ace_languages.php
index d6d80f5..ea3694c 100644
--- a/htdocs/application/config/ace_languages.php
+++ b/htdocs/application/config/ace_languages.php
@@ -26,6 +26,7 @@ $config['ace_languages'] = array(
 	'latex' => 'latex',
 	'sql' => 'sql',
 	'xml' => 'xml',
+	'0' => 'text',
 	'abap' => 'abap',
 	'actionscript' => 'actionscript',
 	'actionscript3' => 'actionscript',
@@ -43,7 +44,6 @@ $config['ace_languages'] = array(
 	'c_mac' => 'c_cpp',
 	'c_winapi' => 'c_cpp',
 	'csharp' => 'csharp',
-	'css' => 'css',
 	'd' => 'd',
 	'dart' => 'dart',
 	'dot' => 'dot',
diff --git a/htdocs/themes/default/js/stikked.js b/htdocs/themes/default/js/stikked.js
index 5f66c29..93d67cc 100644
--- a/htdocs/themes/default/js/stikked.js
+++ b/htdocs/themes/default/js/stikked.js
@@ -275,7 +275,15 @@ ST.ace_init = function() {
 
 ST.ace_setlang = function() {
     var lang = $('#lang').val();
-    var mode = ST.ace_modes[lang];
+    var mode = '';
+    try {
+        mode = ST.ace_modes[lang];
+    } catch (undefined) {
+        mode = 'text';
+    }
+    if (mode === undefined) {
+        mode = 'text';
+    }
     ST.ace_editor.getSession().setMode("ace/mode/" + mode);
 }