diff --git a/snappymail/v/0.0.0/app/libraries/RainLoop/Service.php b/snappymail/v/0.0.0/app/libraries/RainLoop/Service.php
index 2ea43f5f4..0a69e6c0f 100644
--- a/snappymail/v/0.0.0/app/libraries/RainLoop/Service.php
+++ b/snappymail/v/0.0.0/app/libraries/RainLoop/Service.php
@@ -41,6 +41,7 @@ class Service
 
 		\header('Referrer-Policy: no-referrer');
 		\header('X-Content-Type-Options: nosniff');
+		\header('Permissions-Policy: interest-cohort=()');
 
 		$sContentSecurityPolicy = \trim($this->oActions->Config()->Get('security', 'content_security_policy', '')) ?: APP_DEFAULT_CSP;
 		if ($this->oActions->Config()->Get('security', 'use_local_proxy_for_external_images', '')) {