color-picker-appearance-color-well-drag.html

<!DOCTYPE html>
<meta name=fuzzy content="maxDifference=0-3; totalPixels=0-1000">
<script src="../../../resources/testdriver.js"></script>
<script src="../../../resources/testdriver-vendor.js"></script>
<script src="../resources/picker-common.js"></script>

<input type='color' value='#80D9FF'>

<script>
  window.onload = openPickerAppearanceOnly(document.querySelector('input'),() => {
    internals.pagePopupWindow.focus();
    const popupDocument = internals.pagePopupWindow.document;
    const colorWell = popupDocument.querySelector('color-well');
    const colorWellRect = colorWell.getBoundingClientRect();
    eventSender.mouseMoveTo(colorWellRect.left, colorWellRect.top);
    eventSender.mouseDown();
    eventSender.mouseMoveTo(colorWellRect.left + (colorWellRect.width * 4 / 10), colorWellRect.top + (colorWellRect.height * 6 / 10));
    eventSender.mouseUp();
  });
</script>

chromium/third_party/blink/web_tests/fast/forms/color/color-picker-appearance-color-well-drag.html