chromium/third_party/blink/web_tests/svg/custom/rgba-color-outline.svg

<svg xmlns="http://www.w3.org/2000/svg" width="200" height="200">
<style>
rect { outline: 50px solid rgba(0,0,255,0.5); }
</style>
<rect x="50" y="50" width="1" height="1" fill="rgba(0,0,255,0.5)"/>
</svg>