testfs

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">

<head>
    <title>sense fullscreen</title>
    <meta http-equiv="content-type" content="text/html;charset=utf-8" />
    <meta name="generator" content="Geany 1.32" />
</head>

<body >
    <div id="fullscreendiv" class="fullscreendiv"> Fullscreendiv!   </div>
    <div id="notfullscreendiv" class="notfullscreendiv"> Not fullscreendiv! </div>
    <script>
        var isFullscreen = false;
        window.addEventListener('resize', function () {
            console.log("window.innerHeight:" + window.innerHeight + " screen.height:" + screen.height);
            if (window.innerHeight > (screen.height - 10)) {
                isFullscreen = true;
                yourFunction();
            } else {
                isFullscreen = false;
                yourFunction();
                };
        }, false);

    function yourFunction() {
        if(isFullscreen) {
            document.getElementById('notfullscreendiv').style.display = "none";
            document.getElementById('fullscreendiv').style.display = "block";
            console.log('isFullscreen');
            console.log('window.innerHeight:' + window.innerHeight + 'screen.height:' + screen.height)
        } else {
            document.getElementById('notfullscreendiv').style.display = "block";
            document.getElementById('fullscreendiv').style.display = "none";
            console.log('isnotFullscreen');
            console.log('window.innerHeight:' + window.innerHeight + 'screen.height:' + screen.height);
        };
    };
    window.dispatchEvent(new Event('resize'));
    </script>
</body>
</html>