chromium/third_party/blink/web_tests/external/wpt/css/css-contain/contain-paint-023.html

<!DOCTYPE html>

  <meta charset="UTF-8">

  <title>CSS Containment Test: 'contain: paint' and absolutely positioned descendants</title>

  <link rel="author" title="GĂ©rard Talbot" href="http://www.gtalbot.org/BrowserBugsSection/css21testsuite/">
  <link rel="help" href="https://www.w3.org/TR/css-contain-1/#containment-paint">
  <link rel="match" href="../reference/ref-filled-green-100px-square.xht">

  <meta content="This test checks that paint containment applies to atomic inline elements so that they can act as containing block for absolutely positioned descendants." name="assert">

  <link rel="stylesheet" type="text/css" href="/fonts/ahem.css" />
  <style>
  div#rel-pos-red
    {
      background-image: url("support/pattern-gg-gr-100x100.png");
      color: green;
      font-family: Ahem;
      font-size: 50px;
      height: 2em;
      line-height: 1;
      position: relative;
      width: 2em;
    }

  div#containing-block
    {
      contain: paint;
      display: inline-block;
      height: 50%;
      vertical-align: top;
      width: 50%;
    }

  div#abspos
    {
      background-color: green;
      height: 50px;
      position: absolute;
      left: 0px;
      width: 50px;
    }
  </style>

  <p>Test passes if there is a filled green square and <strong>no red</strong>.

  <div id="rel-pos-red">

    AB C<div id="containing-block">

      <div id="abspos"></div>

    </div>

  </div>

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    |  C |c-b|
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