diff --git a/tests/PHPUnit/proxy/index.php b/tests/PHPUnit/proxy/index.php
index 70e99b6fe601e7f423e60849c102a1e01b02c1ba..712c0c16566ed6fcb2ebe6c94bfe44e4eabf25ff 100644
--- a/tests/PHPUnit/proxy/index.php
+++ b/tests/PHPUnit/proxy/index.php
@@ -35,7 +35,7 @@ function loadAllPluginsButOneTheme()
 
     $themesNotToEnable = array('ExampleTheme', 'LeftMenu', 'PleineLune');
 
-    $enableMorpheus = empty($_REQUEST['morpheus']);
+    $enableMorpheus = !empty($_REQUEST['morpheus']);
     if (!$enableMorpheus) {
         $themesNotToEnable[] = 'Morpheus';
     }