diff --git a/system/src/Grav/Common/Cache.php b/system/src/Grav/Common/Cache.php
index <HASH>..<HASH> 100644
--- a/system/src/Grav/Common/Cache.php
+++ b/system/src/Grav/Common/Cache.php
@@ -64,7 +64,7 @@ class Cache extends Getters
         $this->enabled = (bool) $this->config->get('system.cache.enabled');
 
         // Cache key allows us to invalidate all cache on configuration changes.
-        $this->key = substr(md5(($prefix ? $prefix : 'g') . $uri->rootUrl(true) . $this->config->key . GRAV_VERSION), 2, 8);
+        $this->key = substr(md5(($prefix ? $prefix : 'g') . $uri->rootUrl(true) . $this->config->key() . GRAV_VERSION), 2, 8);
 
         $this->driver = $this->getCacheDriver();
 
diff --git a/system/src/Grav/Common/Config/Config.php b/system/src/Grav/Common/Config/Config.php
index <HASH>..<HASH> 100644
--- a/system/src/Grav/Common/Config/Config.php
+++ b/system/src/Grav/Common/Config/Config.php
@@ -105,6 +105,11 @@ class Config extends Data
         $this->check();
     }
 
+    public function key()
+    {
+        return $this->checksum;
+    }
+
     public function reload()
     {
         $this->check();
Add back configuration key to caching (was accidentally removed)