Create a makeshift play event for the Vimeo Player API while autoplay/background embed option is enabled.

index.html

<div id="made-in-ny"></div>

<script src="https://player.vimeo.com/api/player.js"></script>
<script>
    var options = {
        url: 'https://vimeo.com/272406014',
        width: 640,
        loop: true,
        autoplay: true, // Notice autoplay is enabled.
        muted: true, // The video has been muted due to new Chrome/Safari autoplay conditions.
        background: true, // This will also work for the background option.
    };

    var player = new Vimeo.Player('made-in-ny', options);

    // As you can see, this does not fire when the autoplay/background embed option is enabled.
    player.on('play', function() {
        console.log('You will not see this in the console.');
    });
    
    // Set a variable to track if the video is playing or not.
    var isPlaying = false;

    // Place your code that you want to run on the makeshift play event here.
    function onPlay() {
        console.log('Yay! a play event!');
    }

    /**
     * Use the timeupdate event instead of the play event due to 
     * the play event not firing when using the autoplay or background
     * embed option.
     * 
     * @param {Object} data The curent duration, percent, and seconds.
     * {@link https://github.com/vimeo/player.js#timeupdate Vimeo Player API timeupdate Event}
     */
    player.on('timeupdate', function(data) {
        // If isPlaying has already been set to true, quit.
        if (isPlaying === true) {
            return;
        }

        // If the video has past 0.00 seconds, set isPlaying to true and run the onPlay() function.
        if (data['seconds'] > 0) {
            isPlaying = true;
            onPlay();
        }
    });
</script>