diff --git a/lib/htmlpurifier/HTMLPurifier/Printer/HTMLDefinition.php b/lib/htmlpurifier/HTMLPurifier/Printer/HTMLDefinition.php
index 679d19ba3a1..c18cd95d5e2 100644
--- a/lib/htmlpurifier/HTMLPurifier/Printer/HTMLDefinition.php
+++ b/lib/htmlpurifier/HTMLPurifier/Printer/HTMLDefinition.php
@@ -43,8 +43,8 @@ class HTMLPurifier_Printer_HTMLDefinition extends HTMLPurifier_Printer
         $ret .= $this->element('caption', 'Doctype');
         $ret .= $this->row('Name', $doctype->name);
         $ret .= $this->row('XML', $doctype->xml ? 'Yes' : 'No');
-        $ret .= $this->row('Default Modules', implode($doctype->modules, ', '));
-        $ret .= $this->row('Default Tidy Modules', implode($doctype->tidyModules, ', '));
+        $ret .= $this->row('Default Modules', implode(', ', $doctype->modules));
+        $ret .= $this->row('Default Tidy Modules', implode(', ', $doctype->tidyModules));
         $ret .= $this->end('table');
         return $ret;
     }
diff --git a/lib/htmlpurifier/readme_moodle.txt b/lib/htmlpurifier/readme_moodle.txt
index 1195367485d..d0f76044dbf 100644
--- a/lib/htmlpurifier/readme_moodle.txt
+++ b/lib/htmlpurifier/readme_moodle.txt
@@ -21,3 +21,5 @@ Modifications:
   Check status of https://github.com/ezyang/htmlpurifier/pull/148
 * MDL-67030 applied https://github.com/ezyang/htmlpurifier/pull/224 towards
   php74 compatibility.
+* MDL-67115 applied https://github.com/ezyang/htmlpurifier/pull/243 towards
+  php74 compatibility.