diff --git a/lib/formslib.php b/lib/formslib.php
index f75a75ca517..daeeb4a5981 100644
--- a/lib/formslib.php
+++ b/lib/formslib.php
@@ -2889,7 +2889,7 @@ class MoodleQuickForm_Rule_Required extends HTML_QuickForm_Rule {
         }
         $stripvalues = array(
             '#</?(?!img|canvas|hr).*?>#im', // all tags except img, canvas and hr
-            '#(\xc2|\xa0|\s|&nbsp;)#', //any whitespaces actually
+            '#(\xc2\xa0|\s|&nbsp;)#', // Any whitespaces actually.
         );
         if (!empty($CFG->strictformsrequired)) {
             $value = preg_replace($stripvalues, '', (string)$value);
diff --git a/lib/tests/formslib_test.php b/lib/tests/formslib_test.php
index 1ad2776bd31..18e5edc5792 100644
--- a/lib/tests/formslib_test.php
+++ b/lib/tests/formslib_test.php
@@ -51,6 +51,8 @@ class core_formslib_testcase extends advanced_testcase {
         $this->assertTrue($rule->validate("Something\nmore"));
         $this->assertTrue($rule->validate("\nmore"));
         $this->assertTrue($rule->validate(" more "));
+        $this->assertTrue($rule->validate('ш'));
+        $this->assertTrue($rule->validate("の"));
         $this->assertTrue($rule->validate("0"));
         $this->assertTrue($rule->validate(0));
         $this->assertTrue($rule->validate(true));
@@ -88,6 +90,8 @@ class core_formslib_testcase extends advanced_testcase {
         $this->assertTrue($rule->validate("\nmore"));
         $this->assertTrue($rule->validate(" more "));
         $this->assertTrue($rule->validate("0"));
+        $this->assertTrue($rule->validate('ш'));
+        $this->assertTrue($rule->validate("の"));
         $this->assertTrue($rule->validate(0));
         $this->assertTrue($rule->validate(true));
         $this->assertTrue($rule->validate('<p>x</p>'));