fullscreen/api/document-exit-fullscreen.html

<!DOCTYPE html>
<title>Document#exitFullscreen()</title>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="/resources/testdriver.js"></script>
<script src="/resources/testdriver-vendor.js"></script>
<script src="../trusted-click.js"></script>
<div id="log"></div>
<body></body>
<script>
    promise_test(async function (t) {
        const div = document.querySelector("div");
        // enter fullscreen
        await trusted_request(div);

        // Exit fullscreen
        const [event] = await Promise.all([
            fullScreenChange(),
            document.exitFullscreen(),
        ]);

        // Check event from exiting fullscreen
        assert_equals(event.target, div, "event.target");
        assert_true(event.bubbles, "event.bubbles");
        assert_false(event.cancelable, "event.cancelable");
        assert_true(event.composed, "event.composed");
    }, "Checks that the fullscreenchange event is fired when exiting fullscreen");
</script>