Used this script in page header
<script language=”JavaScript”>
// mozfullscreenerror event handler
function errorHandler() {
alert(‘mozfullscreenerror’);
}
document.documentElement.addEventListener(‘mozfullscreenerror’, errorHandler, false);
// toggle full screen
function toggleFullScreen() {
if (!document.fullscreenElement && // alternative standard method
!document.mozFullScreenElement && !document.webkitFullscreenElement) { // current working methods
if (document.documentElement.requestFullscreen) {
document.documentElement.requestFullscreen();
} else if (document.documentElement.mozRequestFullScreen) {
document.documentElement.mozRequestFullScreen();
} else if (document.documentElement.webkitRequestFullscreen) {
document.documentElement.webkitRequestFullscreen(Element.ALLOW_KEYBOARD_INPUT);
}
} else {
if (document.cancelFullScreen) {
document.cancelFullScreen();
} else if (document.mozCancelFullScreen) {
document.mozCancelFullScreen();
} else if (document.webkitCancelFullScreen) {
document.webkitCancelFullScreen();
}
}
}
// keydown event handler
document.addEventListener('keydown', function(e) {
if (e.keyCode == 0 ) { // F11 key
toggleFullScreen();
}
}, false);
// End -->
</script>
To insert the script I used Header and Footer Scripts plugin.
Topic resolved.