diff --git a/php/elFinderVolumeDropbox2.class.php b/php/elFinderVolumeDropbox2.class.php
index f23551710..f00d79c8f 100644
--- a/php/elFinderVolumeDropbox2.class.php
+++ b/php/elFinderVolumeDropbox2.class.php
@@ -363,7 +363,7 @@ public function netmountPrepare($options)
                     if ($code && $state) {
                         if (!empty($options['id'])) {
                             // see https://github.com/kunalvarma05/dropbox-php-sdk/issues/115
-                            $authHelper->getPersistentDataStore()->set('state', filter_var($state, FILTER_SANITIZE_STRING));
+                            $authHelper->getPersistentDataStore()->set('state', htmlspecialchars($state));
                             $tokenObj = $authHelper->getAccessToken($code, $state, $callback);
                             $options['tokens'] = [
                                 'access_token' => $tokenObj->getToken(),