Web player fullscreen and focus.

I am trying to enable fullscreen through a javascript button on my HTML page. The button works fine to do things like debug logs and playing audio files, but because the web player is not in focus when the button is pressed - the web player does not go into fullscreen mode (I see this is for security reasons).

Is there any way to have my button work so that when the button is clicked the fullscreen state is stored, so you click on the web player and it then goes into fullscreen mode.

My current code is just what usually works when in focus.

 function Max()
 {
     Screen.fullScreen = !Screen.fullScreen; 
 }