src/de/steamwar/bungeecore/listeners/ChatListener.java

@@ -131,7 +131,7 @@ public class ChatListener extends BasicListener {
             return true;
         }
 
-        if(message.replace("§[a-f0-9klmno]", "").trim().isEmpty()) {
+        if(message.replace("§[a-f0-9klmno]", "").strip().isEmpty()) {
             sender.system("CHAT_EMPTY");
             return true;
         }