diff --git a/assets/backend.css b/assets/backend.css
new file mode 100644
index 00000000..72be5dac
--- /dev/null
+++ b/assets/backend.css
@@ -0,0 +1,3 @@
+#tl_navigation .tl_level_1_group .group-notification_center {
+    background: url(notification.png) 8px center no-repeat;
+}
\ No newline at end of file
diff --git a/bin/queue b/bin/queue
index e1396f49..9a99599b 100755
--- a/bin/queue
+++ b/bin/queue
@@ -1,5 +1,4 @@
 #!/usr/bin/env php
-
 <?php
 
 /**
diff --git a/config/config.php b/config/config.php
index ac0296ec..ae9bc974 100644
--- a/config/config.php
+++ b/config/config.php
@@ -34,6 +34,11 @@
     )
 ));
 
+// Load icon in Contao 4.2 backend
+if ('BE' === TL_MODE) {
+    $GLOBALS['TL_CSS'][] = 'system/modules/notification_center/assets/backend.css';
+}
+
 /**
  * Front end modules
  */
diff --git a/library/NotificationCenter/Model/Message.php b/library/NotificationCenter/Model/Message.php
index 8377dcbe..13dcc3c2 100644
--- a/library/NotificationCenter/Model/Message.php
+++ b/library/NotificationCenter/Model/Message.php
@@ -43,7 +43,7 @@ public function send(array $arrTokens, $strLanguage = '')
 
         if (isset($GLOBALS['TL_HOOKS']['sendNotificationMessage']) && is_array($GLOBALS['TL_HOOKS']['sendNotificationMessage'])) {
             foreach ($GLOBALS['TL_HOOKS']['sendNotificationMessage'] as $arrCallback) {
-                $blnSuccess = \System::importStatic($arrCallback[0])->$arrCallback[1]($this, $arrTokens, $strLanguage, $objGatewayModel);
+                $blnSuccess = \System::importStatic($arrCallback[0])->{$arrCallback[1]}($this, $arrTokens, $strLanguage, $objGatewayModel);
 
                 if (!$blnSuccess) {
                     return false;