svg-as-background-image-dynamic-color-scheme.html

<!doctype html>
<head>
  <title>prefers-color-scheme inside an SVG image dynamically becoming dark</title>
</head>
<p>There should be a green square below.</p>
<div style="background: url(resources/prefers-color-scheme.svg); height: 100px; width: 100px;"></div>
<script src="../resources/run-after-layout-and-paint.js"></script>
<script>
    function endTest() {
        if (window.testRunner)
            testRunner.notifyDone();
    }

    function doTest() {
        window.internals.setDarkPreferredColorScheme(document);
        runAfterLayoutAndPaint(endTest);
    }

    runAfterLayoutAndPaint(doTest);

    if (window.testRunner)
        testRunner.waitUntilDone();
</script>

chromium/third_party/blink/web_tests/paint/svg-as-background-image-dynamic-color-scheme.html