Custom full Screen button to scale up browser screen

As we were able to do full screen of course in Storyline 2, but the same functionality we want to build in new version Storyline 3, but the following codebase is not working for us which was working fine in earlier version Storyline 2:

fullscreen = document.webkitIsFullScreen || document.msFullscreenElement || document.mozFullScreen;
element = document.documentElement;
if(!fullscreen){
 if(element.requestFullscreen) {
 element.requestFullscreen();
 } else if(element.mozRequestFullScreen) {
 element.mozRequestFullScreen();
 } else if(element.webkitRequestFullScreen) {
 element.webkitRequestFullscreen();
 } else if(element.msRequestFullscreen) {
 element.msRequestFullscreen();
 }
window.globals.scale = 'show all';
window.globals.strScale = 'show all';
player.initGlobals();
 }else{
 if(document.exitFullscreen) {
 document.exitFullscreen();
 } else if(document.mozCancelFullScreen) {
 document.mozCancelFullScreen();
 } else if(document.webkitExitFullscreen) {
 document.webkitExitFullscreen();
 }else if(document.msExitFullscreen){
 document.msExitFullscreen();
 }
window.globals.scale = 'noscale';
window.globals.strScale = 'noscale';
player.initGlobals();
 }

After done some research on this I found the highlighted statement "player.initGlobals()" in above codebase that is not supported in Storyline 3.

Can anyone helps us in this issue, how to initialize globals values using JavaScript in Storyline 3

Thanks in Advance!!