No default groupNot An Issue
So, I had better chat working went to restart the server now every time someone not in my vip or moderator group I get a message in rcon like this.

Player xxxxxxx doesnt seem to be in any better chat group. Falling back to default group.
This should never happen make sure you have a group named default.

Well I do have a group named that.... what is happening 

Every player needs to be at least in one group for the plugin to determine what the message should look like.

For this, you always need a Better Chat group called "default" and not forcibly remove players from the "default" group, since oxide automatically adds them to it.

If this aspect is respected, you should not be getting the warnings you're getting.

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