css/css-multicol/multicol-zero-height-003.html

<!DOCTYPE html>
<meta charset="utf-8">
<title>CSS Multi-column Test: Test a block element with box-decoration-break:clone in a zero height multi-column container</title>
<link rel="author" title="Ting-Yu Lin" href="mailto:tlin@mozilla.com">
<link rel="author" title="Mozilla" href="https://www.mozilla.org/">
<link rel="help" href="https://drafts.csswg.org/css-break/#breaking-rules">
<link rel="help" href="https://drafts.csswg.org/css-break/#break-decoration">
<link rel="help" href="https://bugzilla.mozilla.org/show_bug.cgi?id=1693616">
<link rel="help" href="https://bugzilla.mozilla.org/show_bug.cgi?id=1754598">
<link rel="match" href="multicol-zero-height-003-ref.html">
<meta name="assert" content="This test verifies that a block element with box-decoration-break:clone can make progress when fragmenting in a zero height multi-column container. Also, it should expend 1px of its content-box per fragment, and therefore should only need to create 2 fragments.">

<style>
.multicol {
  column-width: 100px;
  inline-size: 300px;
  block-size: 0;
}

.child {
  color: green;
  inline-size: 100px;
  block-size: 2px;
  border: 5px solid green;
  box-decoration-break: clone;
}
</style>

<!-- WARNING: This test hangs Firefox version < 99 without the fix in bug 1754598. -->

<p>There shouldn't be a green strip in the third column.</p>
<div class="multicol">
  <div class="child"></div>
</div>