added a filter for messages without user information

src/state/handler.rs

@@ -70,7 +70,7 @@ type DynHanlder<T> = Box<
         + Send,
 >;
 
-pub struct Handler<T> {
+pub struct Handler<T: ?Sized> {
     pub func: Option<DynHanlder<T>>,
 
     pub previous: MessageIds,