Merge pull request #416 from juban/fix-missing-dynamic-custom-fields-…

…objects

Fix #415 for missing dynamic custom fields

src/models/data/SeoData.php

@@ -438,7 +438,7 @@ private function _getVariables ()
 
 		if ($this->_element !== null)
 		{
-			foreach ($this->_element->attributes() as $name)
+			foreach (array_keys($this->_element->fields()) as $name)
 				if ($name !== $this->_handle)
 					$variables[$name] = $this->_element->$name ?? null;