diff --git a/src/Plugin/views/relationship/FlagViewsRelationship.php b/src/Plugin/views/relationship/FlagViewsRelationship.php
index 81d0964..2e1e3ef 100644
--- a/src/Plugin/views/relationship/FlagViewsRelationship.php
+++ b/src/Plugin/views/relationship/FlagViewsRelationship.php
@@ -138,11 +138,10 @@ class FlagViewsRelationship extends RelationshipPluginBase {
         // Disable page caching for anonymous users.
         $this->pageCacheKillSwitch->trigger();
 
-        // Add in the SID from Session API for anonymous users.
+        // Check on PHP session id for anonymous users
         $this->definition['extra'][] = [
-          'field' => 'sid',
-          'value' => '***FLAG_CURRENT_USER_SID***',
-          'numeric' => TRUE,
+          'field' => 'session_id',
+          'value' => session_id(),
         ];
       }
     }