Fix warning

htdocs/core/modules/mailings/contacts1.modules.php

@@ -309,7 +309,7 @@ class mailing_contacts1 extends MailingTargets
 
 		// Choose language if multilangue active
 
-		if (@$conf->global->MAIN_MULTILANGS==1) {
+		if (getDolGlobalInt('MAIN_MULTILANGS') == 1) {
 			require_once DOL_DOCUMENT_ROOT.'/core/class/html.formadmin.class.php';
 			$formadmin = new FormAdmin($this->db);
 			$s .= '<span class="opacitymedium">'.$langs->trans("DefaultLang").':</span> ';