Declare dynamic class property

includes/form-actions/cfafa-form-action-email.php

@@ -65,6 +65,15 @@ class CFAFA_Form_Action_Email extends CFAFA_Form_Action_Base {
 	 */
 	public $field_name = 'cfafa_email_';
 
+	/**
+	 * Array of translatable mapped Email Fields.
+	 *
+	 * @since 0.1
+	 * @access public
+	 * @var array
+	 */
+	public $mapped_email_fields = [];
+
 	/**
 	 * Constructor.
 	 *