Peace And Quiet 

I'm not familiar with Prat as I have never used it. This addon just leaves and joins channels such as General and Trade based on your settings and your location in game.

I looked at both approaches and I think it is simpler and safer to just update the addon so you can get the chat window to manage if you are doing something non-standard. If I were to automatically manage the channels, there are possible issues, plus someone may actually want a window just for LFG but also have it turn on and off automatically via the addon.

There should be a 9.0.8-alpha1 out soon that add options to change the chat window used to manage each channel. Let me know how it works for you. So far it works well for me.

I have been having the same issue. I'm debating two fixes. Either allowing a configurable chat window to manage per channel or try to do it automatically. I was a little worried about doing it automatically since it only works correctly if it always sees the correct state. If you have any input on it, let me know.

I'll put out a fix soon with one of the solutions.