diff --git a/CHANGELOG.md b/CHANGELOG.md
index 774ee9a..dc64b3d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,6 +1,10 @@
 # Change Log
 All notable changes to this project will be documented in this file.
 
+## [1.4.1] - 2024-06-19
+### Updated
+- Fixed compatibility with PHP 5.6.
+
 ## [1.4.0] - 2024-04-26
 ### Added
 - GitHub actions CI workflow.
diff --git a/classes/local_contact.php b/classes/local_contact.php
index 610cca3..ea99615 100644
--- a/classes/local_contact.php
+++ b/classes/local_contact.php
@@ -91,8 +91,8 @@ public function __construct() {
                 $this->fromemail = required_param('email', PARAM_TEXT);
             }
         }
-        $this->fromname = trim($this->fromname ?? '');
-        $this->fromemail = trim($this->fromemail ?? '');
+        $this->fromname = isset($this->fromname) ? trim($this->fromname) : '';
+        $this->fromemail = isset($this->fromemail) ? trim($this->fromemail) : '';
 
         $this->isspambot = false;
         $this->errmsg = '';
@@ -247,7 +247,7 @@ public function __construct() {
      */
     private function makeemailuser($email, $name = '', $id = -99) {
         $emailuser = new stdClass();
-        $emailuser->email = trim(filter_var($email, FILTER_SANITIZE_EMAIL) ?? '');
+        $emailuser->email = trim(filter_var($email, FILTER_SANITIZE_EMAIL) ? filter_var($email, FILTER_SANITIZE_EMAIL) : '');
         if (!filter_var($email, FILTER_VALIDATE_EMAIL)) {
             $emailuser->email = '';
         }
@@ -310,7 +310,7 @@ public function sendmessage($email, $name, $sendconfirmationemail = false) {
          * @return boolean true if string is not empty, otherwise false.
          */
         function filterempty($string) {
-            $string = trim($string ?? '');
+            $string = isset($string) ? trim($string) : '';
             return ($string !== null && $string !== false && $string !== '');
         }
 
diff --git a/index.php b/index.php
index 696be4b..c367f8b 100644
--- a/index.php
+++ b/index.php
@@ -66,8 +66,8 @@
 
 // The default recipient is the Moodle site's support contact. This will
 // be used if no recipient was specified or if the recipient is unknown.
-$name = trim($CFG->supportname ?? '');
-$email = trim($CFG->supportemail ?? '');
+$name = isset($CFG->supportname) ? trim($CFG->supportname) : '';
+$email = isset($CFG->supportemail) ? trim($CFG->supportemail) : '';
 
 // Handle recipient alias.
 // If the form includes a recipient's alias, search the plugin's recipient list settings for a name and email address.
@@ -75,7 +75,7 @@
 if (!empty($recipient)) {
     $lines = explode("\n", get_config('local_contact', 'recipient_list'));
     foreach ($lines as $linenumbe => $line) {
-        $line = trim($line ?? '');
+        $line = isset($line) ? trim($line) : '';
         if (empty($line)) { // Blank line.
             continue;
         }
diff --git a/version.php b/version.php
index 7941855..907d24a 100644
--- a/version.php
+++ b/version.php
@@ -25,9 +25,9 @@
 
 defined('MOODLE_INTERNAL') || die();
 
-$plugin->version   = 2024042600;        // The current module version (Date: YYYYMMDDXX).
+$plugin->version   = 2024061900;        // The current module version (Date: YYYYMMDDXX).
 $plugin->requires  = 2015111600;        // Requires Moodle version 3.0.
 $plugin->component = 'local_contact';   // To check on upgrade, that module sits in correct place.
-$plugin->release   = '1.4.0';
+$plugin->release   = '1.4.1';
 $plugin->maturity  = MATURITY_STABLE;
 $plugin->cron      = 0;