mortenpi/katex-bug.html

## katex-bug.html
<!DOCTYPE html>
<html lang="en">

  <head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>KaTeX rendering bug example</title>
    <link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/katex@0.10.2/dist/katex.min.css" integrity="sha384-yFRtMMDnQtDRO8rLpMIKrtPCD5jdktao2TV19YiZYWMDkUR5GQZR/NOVTdquEx1j" crossorigin="anonymous">
    <script defer src="https://cdn.jsdelivr.net/npm/katex@0.10.2/dist/katex.min.js" integrity="sha384-9Nhn55MVVN0/4OFx7EE5kpFBPsEMZxKTCnA+4fqDmg12eCTqGi6+BB2LjY8brQxJ" crossorigin="anonymous"></script>
    <script defer src="https://cdn.jsdelivr.net/npm/katex@0.10.2/dist/contrib/auto-render.min.js" integrity="sha384-kWPLUVMOks5AQFrykwIup5lo0m3iMkkHrD0uJ4H5cjeGihAutqP0yW0J6dpFiVkI" crossorigin="anonymous" onload="renderMathInElement(document.body);"></script>

    <style>
      #container {
        height: 60vh;
        border: 1px solid black;
        overflow-y: scroll;
        padding: 1rem;
      }

      .quarter-block {
        height: 25vh;
        border-left: 1px dashed black;
        margin: 1rem 0;
        text-align: center;
      }

    </style>

    <style id="fixedstyle" onload="this.disabled = true;">
      .katex .katex-mathml {
        position: fixed;
      }

    </style>
  </head>

  <body>

    <h1>KaTeX rendering bug example</h1>

    <div id="container">
      <h1>Some filler content</h1>
      <p class="quarter-block">...</p>
      <p class="quarter-block">...</p>
      <p class="quarter-block">...</p>
      <p class="quarter-block">...</p>
      <h2>Equation comes here</h2>
      \[ E = mc^2 \]
      <h2>Maybe more content</h2>
      <p class="quarter-block">...</p>
      <p class="quarter-block">...</p>
    </div>

    <p>
      As all the content is in a scrollable container, the outer main viewport should not scroll.
    </p>
    <p>
      But the <code>position: absolute;</code> in the <code>.katex .katex-mathml</code> class creates elements that exist outside the scrollable container, but are positioned far down on the page.
    </p>

    <p>
      The offender is the <code>&lt;span class="katex-mathml"&gt;</code> element, a child of the equation span.
    </p>

    <button onclick="document.getElementById('fixedstyle').disabled = false;">Set <code>position</code> to <code>fixed</code></button>
    <button onclick="document.getElementById('fixedstyle').disabled = true;">Set <code>position</code> back to default (<code>fixed</code>)</button>

  </body>

</html>
	<!DOCTYPE html>
	<html lang="en">

	<head>
	<meta charset="UTF-8">
	<meta name="viewport" content="width=device-width, initial-scale=1.0">
	<title>KaTeX rendering bug example</title>
	<link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/katex@0.10.2/dist/katex.min.css" integrity="sha384-yFRtMMDnQtDRO8rLpMIKrtPCD5jdktao2TV19YiZYWMDkUR5GQZR/NOVTdquEx1j" crossorigin="anonymous">
	<script defer src="https://cdn.jsdelivr.net/npm/katex@0.10.2/dist/katex.min.js" integrity="sha384-9Nhn55MVVN0/4OFx7EE5kpFBPsEMZxKTCnA+4fqDmg12eCTqGi6+BB2LjY8brQxJ" crossorigin="anonymous"></script>
	<script defer src="https://cdn.jsdelivr.net/npm/katex@0.10.2/dist/contrib/auto-render.min.js" integrity="sha384-kWPLUVMOks5AQFrykwIup5lo0m3iMkkHrD0uJ4H5cjeGihAutqP0yW0J6dpFiVkI" crossorigin="anonymous" onload="renderMathInElement(document.body);"></script>

	<style>
	#container {
	height: 60vh;
	border: 1px solid black;
	overflow-y: scroll;
	padding: 1rem;
	}

	.quarter-block {
	height: 25vh;
	border-left: 1px dashed black;
	margin: 1rem 0;
	text-align: center;
	}

	</style>

	<style id="fixedstyle" onload="this.disabled = true;">
	.katex .katex-mathml {
	position: fixed;
	}

	</style>
	</head>

	<body>

	<h1>KaTeX rendering bug example</h1>

	<div id="container">
	<h1>Some filler content</h1>
	<p class="quarter-block">...</p>
	<p class="quarter-block">...</p>
	<p class="quarter-block">...</p>
	<p class="quarter-block">...</p>
	<h2>Equation comes here</h2>
	\[ E = mc^2 \]
	<h2>Maybe more content</h2>
	<p class="quarter-block">...</p>
	<p class="quarter-block">...</p>
	</div>

	<p>
	As all the content is in a scrollable container, the outer main viewport should not scroll.
	</p>
	<p>
	But the <code>position: absolute;</code> in the <code>.katex .katex-mathml</code> class creates elements that exist outside the scrollable container, but are positioned far down on the page.
	</p>

	<p>
	The offender is the <code><span class="katex-mathml"></code> element, a child of the equation span.
	</p>

	<button onclick="document.getElementById('fixedstyle').disabled = false;">Set <code>position</code> to <code>fixed</code></button>
	<button onclick="document.getElementById('fixedstyle').disabled = true;">Set <code>position</code> back to default (<code>fixed</code>)</button>

	</body>

	</html>