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

<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, 10);
    document.getSelection().addRange(range);

    // Readonly caret selections should not be reported to the compositor.
</script>