How do I make it go away, and stay away?
First thought would be to change the frequency to something that isn't being used. Or just change it by .1 or even .025 could work.
There's an 'Automatic Open ATC Window' setting somewhere in the setup that can be switched off. Can't remember where exactly but probably on the ATC menu.
On top menu bar within a flight. Go to [options], [ATC]. Delete check on Auto open ATC window.
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