Handle better messages with not supported type

[Pedro M. M.]

• toString should return: not supported.

whatshidden/src/msg/message.js

Lines 137 to 140 in bc13866

 export function extract(msgData) { 
     const type = Type[msgData.type]; 
     return type ? new type(msgData) : new Message(msgData); 
 } 

toString() doesn't exist in parent < Messages >, so it will throw an error.