chromium/third_party/blink/web_tests/fast/forms/accent-color/accent-color-no-transparency-expected.html

<!DOCTYPE html>

<p>The alpha component of accent-color should be ignored, and the form control
should be drawn as if alpha fully opaque.</p>

<div>
  <input checked type=checkbox style="accent-color:rgba(255, 0, 0, 1)">
</div>

<div>
  <input checked type=radio style="accent-color:rgba(255, 0, 0, 1)">
</div>

<div>
  <input type=range style="accent-color:rgba(255, 0, 0, 1)">
</div>

<div>
  <progress style="accent-color:rgba(255, 0, 0, 1)" max="100" value="50"> 50% </progress>
</div>