Consider the HTML
<svg> <filter id="sepia"> <feColorMatrix type="matrix" values="0.393 0.769 0.189 0 0 0.349 0.686 0.168 0 0 0.272 0.534 0.131 0 0 0 0 0 1 0"/> </filter> <svg>
and css
.foo { filter: url(#sepia); }
ResourceLoader will convert the above into a relative URL.
We should at the very least blacklist url parsing of the value of the filter css property.