chromium/src/third_party/blink/renderer/core/testing/data/composited_selection_bounds_basic.html

<style>
    @font-face {
        font-family: ahem;
        src: url(Ahem.ttf);
    }
    * {
        font-family: ahem;
    }
</style>
<span id="text">
    The quick brown fox jumped over the lazy dog.
</span>
<script>
    var range = document.createRange();
    var textNode = document.getElementById("text").firstChild;
    range.setStart(textNode, 10);
    range.setEnd(textNode, 35);
    document.getSelection().addRange(range);

    window.expectedResult = [document, 68, 8, 68, 20, document, 368, 8, 368, 20];
</script>