diff --git a/plugins/demo-account/index.php b/plugins/demo-account/index.php
index 0fdf8a6ef..993df2458 100644
--- a/plugins/demo-account/index.php
+++ b/plugins/demo-account/index.php
@@ -77,7 +77,7 @@ class DemoAccountPlugin extends \RainLoop\Plugins\AbstractPlugin
 		}
 	}
 
-	public function FilterSendMessage(&$oMessage)
+	public function FilterSendMessage($oMessage)
 	{
 		if ($oMessage && $this->isDemoAccount($this->Manager()->Actions()->GetAccount()))
 		{
diff --git a/snappymail/v/0.0.0/app/libraries/RainLoop/Utils.php b/snappymail/v/0.0.0/app/libraries/RainLoop/Utils.php
index 7b4b68bf1..ea7d88f3b 100644
--- a/snappymail/v/0.0.0/app/libraries/RainLoop/Utils.php
+++ b/snappymail/v/0.0.0/app/libraries/RainLoop/Utils.php
@@ -81,7 +81,7 @@ class Utils
 
 	public static function Fingerprint() : string
 	{
-		return \md5(empty($_SERVER['HTTP_USER_AGENT']) ? 'RainLoopFingerprint' : $_SERVER['HTTP_USER_AGENT']);
+		return \md5($_SERVER['HTTP_USER_AGENT'] ?: 'RainLoopFingerprint');
 	}
 
 	public static function GetShortToken() : string
diff --git a/snappymail/v/0.0.0/include.php b/snappymail/v/0.0.0/include.php
index 1a24c36ca..6671be999 100644
--- a/snappymail/v/0.0.0/include.php
+++ b/snappymail/v/0.0.0/include.php
@@ -15,7 +15,7 @@
 			}
 
 			// PHP 8
-			if (!\function_exists('str_contains')) {
+			if (!function_exists('str_contains')) {
 				function str_contains(string $haystack, string $needle) : bool
 				{
 					return false !== \strpos($haystack, $needle);
@@ -233,6 +233,10 @@
 			unset($sSalt, $sData, $sInstalled, $sPrivateDataFolderInternalName);
 		}
 
+		if (!isset($_SERVER['HTTP_USER_AGENT'])) {
+			$_SERVER['HTTP_USER_AGENT'] = '';
+		}
+
 		// See https://github.com/kjdev/php-ext-brotli
 		if (!ini_get('zlib.output_compression') && !ini_get('brotli.output_compression')) {
 			if (defined('USE_GZIP')) {