diff --git a/lib/weblib.php b/lib/weblib.php
index 67c351083f2..f6b646886e5 100644
--- a/lib/weblib.php
+++ b/lib/weblib.php
@@ -1296,7 +1296,7 @@ function format_string($string, $striplinks = true, $options = NULL) {
     //We'll use a in-memory cache here to speed up repeated strings
     static $strcache = false;
 
-    if (empty($CFG->version) or $CFG->version < 2010072800 or during_initial_install()) {
+    if (empty($CFG->version) or $CFG->version < 2013051400 or during_initial_install()) {
         // do not filter anything during installation or before upgrade completes
         return $string = strip_tags($string);
     }