How to keep pilot2atc window open in the sim

[stevenpow 2]

 I wanted to know how is it that you can keep the pilot2ATC window within the Sim open and be able to click the buttons within the sim without the pilot2ATC window disappearing.  Now I know that some people say that you have to run the flight simulator in the window mode but I can't do that using triple screens and I have also seen videos of people using pilot2ATC within the sim and they're able to change radio frequencies and start buttons and etc without the pilot2ATC window  disappearing. 

[Dave-Pilot2ATC 870]

It depends on what SIM you're using and how you're using it. 

The new Multi-Window mode of X-Plane turns all monitors used into "full-screen" mode, so P2A cannot stay on top because X-Plane is driving the monitor directly.  So adding a 4th monitor is about the only way I know of to keep it visible in that scenario.