JSFiddle - React, Tailwind, and code Playground

HTML

<div id="wrapper">
    <video id="video-example" poster="http://tribulant.net/lightbox/files/2010/08/image-2.jpg" width="880" height="495" loop>

      <source id='mp4'
        src="http://www.manart.de/fileadmin/schiffchen.mp4"
        type='video/mp4'>
      <source id='ogv'
        src="http://www.manart.de/fileadmin/schiffchen.ogg.ogv"
        type='video/ogg'>
    </video>    
    </div><!--end wrapper-->

    <!-- script src="fileadmin/js.js"></script -->

JavaScript

var vid = document.getElementById('video-example');
// add the listener directly to the video element
vid.addEventListener('mouseover',hoverVideo,false);

function hoverVideo(e) {   
    vid.play();
    vid.addEventListener('mouseout',hideVideo,false);
}

function hideVideo(e) {
    // do whatever you were going to do here, but omitting
    // the method completely causes an exception
    //vid.pause();   
    
    // clean up the listener when finished
    vid.removeEventListener('mouseout', hideVideo);
}