Program: 179142
Project: 179142
Buggy source:
public void onPlayerChat(PlayerChatEvent event){
  String message=event.getMessage();
  User user=new User(plugin,event.getPlayer());
  if (plugin.mainProperties.getBoolean("String_Node_Str",false)) {
    if (user.inChannel()) {
      user.getActiveChannel().sendChat(user,message);
    }
 else {
      user.sendMessage(ChatColor.RED + "String_Node_Str");
    }
    event.setCancelled(true);
    return;
  }
  if (user.isMuted()) {
    event.setCancelled(true);
    user.sendMessage(ChatColor.GRAY + plugin.mainProperties.getString("String_Node_Str","String_Node_Str"));
    return;
  }
  boolean blocked=ChatChecker.checkBlocked(message,plugin);
  if (blocked) {
    event.setCancelled(true);
    user.sendMessage(ChatColor.GRAY + plugin.mainProperties.getString("String_Node_Str","String_Node_Str"));
    return;
  }
  long slowTimeLeft=slow.playerBlocked(user.getName());
  if ((!user.hasPerm("String_Node_Str")) && slow.isEnabled()) {
    if (slowTimeLeft > 0) {
      user.sendMessage(ChatColor.GRAY + "String_Node_Str" + (int)Math.ceil(slowTimeLeft / 1000)+ "String_Node_Str");
      event.setCancelled(true);
      return;
    }
 else {
      slow.playerAdd(user.getName());
    }
  }
  String prefix;
  log.info(user.getName() + "String_Node_Str" + message);
  if (user.getGroup() != null && !(prefix=user.getGroup().getPrefix()).isEmpty()) {
    message=user.getGroup().getPrefixColor() + "String_Node_Str" + prefix+ "String_Node_Str"+ user.getColor()+ user.getName()+ "String_Node_Str"+ ChatColor.WHITE+ message;
    plugin.getServer().broadcastMessage(message);
    event.setCancelled(true);
  }
 else {
    message=user.getColor() + user.getName() + "String_Node_Str"+ ChatColor.WHITE+ message;
    plugin.getServer().broadcastMessage(message);
    event.setCancelled(true);
  }
}

Fixed version (ground truth):
public void onPlayerChat(PlayerChatEvent event){
  String message=event.getMessage();
  User user=User.getUser(plugin,event.getPlayer());
  if (plugin.mainProperties.getBoolean("String_Node_Str",false)) {
    if (user.inChannel()) {
      user.getActiveChannel().sendChat(user,message);
    }
 else {
      user.sendMessage(ChatColor.RED + "String_Node_Str");
    }
    event.setCancelled(true);
    return;
  }
  if (user.isMuted()) {
    event.setCancelled(true);
    user.sendMessage(ChatColor.GRAY + plugin.mainProperties.getString("String_Node_Str","String_Node_Str"));
    return;
  }
  boolean blocked=ChatChecker.checkBlocked(message,plugin);
  if (blocked) {
    event.setCancelled(true);
    user.sendMessage(ChatColor.GRAY + plugin.mainProperties.getString("String_Node_Str","String_Node_Str"));
    return;
  }
  long slowTimeLeft=slow.playerBlocked(user.getName());
  if ((!user.hasPerm("String_Node_Str")) && slow.isEnabled()) {
    if (slowTimeLeft > 0) {
      user.sendMessage(ChatColor.GRAY + "String_Node_Str" + (int)Math.ceil(slowTimeLeft / 1000)+ "String_Node_Str");
      event.setCancelled(true);
      return;
    }
 else {
      slow.playerAdd(user.getName());
    }
  }
  String prefix;
  log.info(user.getName() + "String_Node_Str" + message);
  if (user.getGroup() != null && !(prefix=user.getGroup().getPrefix()).isEmpty()) {
    message=user.getGroup().getPrefixColor() + "String_Node_Str" + prefix+ "String_Node_Str"+ user.getColor()+ user.getName()+ "String_Node_Str"+ ChatColor.WHITE+ message;
    plugin.getServer().broadcastMessage(message);
    event.setCancelled(true);
  }
 else {
    message=user.getColor() + user.getName() + "String_Node_Str"+ ChatColor.WHITE+ message;
    plugin.getServer().broadcastMessage(message);
    event.setCancelled(true);
  }
}