Fix already clean headline

src/scripts/classes/mapping/thread.ts

@@ -193,7 +193,7 @@ export default class Thread {
 
         // Get the title name
         let name = headline;
-        matches.forEach(e => name = name.replace(e, ""));
+        if (matches) matches.forEach(e => name = name.replace(e, ""));
         return name.trim();
     }