diff --git a/system/src/Grav/Common/Twig/TwigExtension.php b/system/src/Grav/Common/Twig/TwigExtension.php
index e6f9a53dc..9df51e8d0 100644
--- a/system/src/Grav/Common/Twig/TwigExtension.php
+++ b/system/src/Grav/Common/Twig/TwigExtension.php
@@ -1363,7 +1363,7 @@ class TwigExtension extends AbstractExtension implements GlobalsInterface
         if ($exists) {
             return false;
         } else {
-            return $this->config->get('theme.' . $var, $default);
+            return Grav::instance()['config']->get('theme.' . $var, $default);
         }
     }