Web Window API | DOM Window fullscreen property

The Window interface has a fullscreen property which tells whether the window is displayed in fullscreen mode or not. Syntax:

BoolVal = windowReference.fullScreen;

Return value:

Boolean

True: If windows is in fullscreen mode.
False: If windows are not in fullscreen mode.

Example :

html

<!DOCTYPE html>
<html>

<head>
    <title>
        Window fullscreen property
    </title>
</head>

<body>
    <center>
        <h1 style="color:green;"> 
                GeeksForGeeks 
            </h1>

        <h2>Window fullscreen property</h2>

        <button onclick="GFGfun();">press</button>
        <script>
            function GFGfun() {
                alert(window.fullScreen);
            }
        </script>
    </center>
</body>

</html>

Output: Window not in fullscreen:

Window in fullscreen:

Browser support:

Firefox 3+

Web Window API | DOM Window fullscreen property

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