| <!DOCTYPE html> | 
 | <html> | 
 | <head> | 
 |     <style> | 
 |         #box { | 
 |             height: 100px; | 
 |             width: 100px; | 
 |             background-color: blue; | 
 |             animation: move 1 1s linear; | 
 |         } | 
 |          | 
 |         @keyframes move { | 
 |             from { transform: translate(0, 0); } | 
 |             50%  { transform: translate(100px, 0); } | 
 |             to   { transform: translate(300px, 0); } | 
 |         } | 
 |     </style> | 
 |     <script> | 
 |         if (window.testRunner) { | 
 |             testRunner.dumpAsText(); | 
 |             testRunner.waitUntilDone(); | 
 |         } | 
 |  | 
 |         window.addEventListener('load', () => { | 
 |             let box = document.getElementById('box'); | 
 |             box.addEventListener('animationstart', () => { | 
 |                 if (window.testRunner) | 
 |                     testRunner.notifyDone(); | 
 |             }); | 
 |         }, false); | 
 |     </script> | 
 | </head> | 
 | <body> | 
 |     <p>This test should not crash.</p> | 
 |     <div id="box"></div> | 
 | </body> | 
 | </html> |