diff --git a/library/Icinga/Web/UrlParams.php b/library/Icinga/Web/UrlParams.php
index 42094bd68..fa1b2a7f3 100644
--- a/library/Icinga/Web/UrlParams.php
+++ b/library/Icinga/Web/UrlParams.php
@@ -256,7 +256,7 @@ class UrlParams
                 foreach ($this->index[$p] as $key) {
                     unset($this->params[$key]);
                 }
-                $this->changed = true;
+                $changed = true;
             }
         }