diff --git a/lib/ajax/ajaxlib.php b/lib/ajax/ajaxlib.php
index 6508c5bec09..f1455fd71b1 100644
--- a/lib/ajax/ajaxlib.php
+++ b/lib/ajax/ajaxlib.php
@@ -907,7 +907,8 @@ class required_js extends linked_requirement {
     }
 
     public function get_html() {
-        return ajax_get_link_to_script($this->url);
+        $attributes = array('type'=>'text/javascript', 'src'=>$this->url);
+        return html_writer::tag('script', $attributes, '') . "\n";
     }
 
     /**
@@ -1276,15 +1277,6 @@ class required_event_handler extends required_js_code {
     }
 }
 
-/**
- * Return the HTML required to link to a JavaScript file.
- * @param $url the URL of a JavaScript file.
- * @return string the required HTML.
- */
-function ajax_get_link_to_script($url) {
-    return '<script type="text/javascript"  src="' . $url . '"></script>' . "\n";
-}
-
 
 /**
  * Returns whether ajax is enabled/allowed or not.
diff --git a/lib/filelib.php b/lib/filelib.php
index 64fa743ab03..37806b97542 100644
--- a/lib/filelib.php
+++ b/lib/filelib.php
@@ -2076,7 +2076,8 @@ function file_modify_html_header($text) {
     $ufo = '';
     if (filter_is_enabled('filter/mediaplugin')) {
         // this script is needed by most media filter plugins.
-        $ufo = ajax_get_link_to_script($CFG->wwwroot . '/lib/ufo.js');
+        $attributes = array('type'=>'text/javascript', 'src'=>$CFG->httpswwwroot . '/lib/ufo.js');
+        $ufo = html_writer::tag('script', $attributes, '') . "\n";
     }
 
     preg_match('/\<head\>|\<HEAD\>/', $text, $matches);