1401992.html (555B)
1 <!doctype html> 2 <html> 3 <head> 4 <style> 5 video { 6 width: 100px; 7 height: 100px; 8 border: 10px solid purple; 9 } 10 fieldset { 11 border: 10px solid blue; 12 } 13 fieldset:valid { 14 border-color: green; 15 } 16 fieldset:invalid { 17 border-color: red; 18 } 19 </style> 20 <script> 21 window.onload = function() { 22 let v = document.getElementById("x"); 23 v.currentTime = -128; 24 v.controls = !v.controls; 25 } 26 </script> 27 </head> 28 <body> 29 <!-- Native anonymous content shouldn't affect fieldset validity --> 30 <fieldset><video id="x" style="visibility:hidden"></video></fieldset> 31 </body> 32 </html>