chromium/src/third_party/blink/web_tests/svg/masking/mask-of-root.html - manifest_repos/chromium_src - Git at Google

 <!doctype HTML>
 <svg mask="url(#m)">
   <mask id="m">
     <rect fill="white" width="100" height="100"/>
   </mask>
   <rect width="100" height="100" fill="green"/>
   <rect width="100" height="100" fill="red" x="100"/>
 </svg>
	<!doctype HTML>
	<svg mask="url(#m)">
	<mask id="m">
	<rect fill="white" width="100" height="100"/>
	</mask>
	<rect width="100" height="100" fill="green"/>
	<rect width="100" height="100" fill="red" x="100"/>
	</svg>