preparing document submission

Signed-off-by: Stephan Richter <s.richter@srsoftware.de>

frontend/src/translations.svelte.js

@@ -8,6 +8,7 @@ export async function loadTranslation(lang){
 }
 
 export function t(key,...args){
+    if (key === undefined) return "";
     if (key instanceof Response) key = 'status.'+key.status;
     let set = translations.values;
     let keys = key.split('.');