<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title>CSS Masking: mask-image: unresovlable mask url</title> <link rel="author" title="CJ Ku" href="mailto:cku@mozilla.com"> <link rel="author" title="Mozilla" href="https://www.mozilla.org"> <link rel="help" href="https://www.w3.org/TR/css-masking-1/#the-mask-image"> <link rel="match" href="blank.html"> <meta name="assert" content="Test checks a mask reference to a none-mask SVG element should be counted as an image layer of transparent black."> <svg height="0"> <clipPath id="clip1"> <circle cx="50" cy="50" r="25"/> </clipPath> </svg> <style type="text/css"> div { background-color: purple; width: 100px; height: 100px; } div.mask-by-reference { mask-image: url(#clip1); } </style> </head> <body> <div class="mask-by-reference"></div> </body> </html>