Try to detect if autoplay on videos is blocked

autoplay_blocked_detector.html

<video id="vid" autoplay loop muted>
    <source src="/vid.mp4" type="video/mp4" />
</video>

<script>
    setTimeout(function() {
        let vid = document.getElementById("vid");
        if (vid.paused) {
            let message = document.createElement("p");
            message.innerHTML = "There's supposed to be a video here, but your browser either " +
                "doesn't support the video element or is blocking autoplay";
            vid.replaceWith(message);
        }
    }, 100);
</script>