<html class="reftest-wait"> <head> <link rel="author" title="Mats Palmgren" href="https://bugzilla.mozilla.org/show_bug.cgi?id=685012"> <link rel="help" href="http://www.w3.org/TR/CSS21/page.html#propdef-page-break-inside"> <meta name="flags" content="paged"> <meta charset="utf-8"> <title>Balancing Overflow, page-break-inside:avoid</title> <style> /* Sets of heights that trigger crash: 100px/50px/51+px 100px/30px/74+px Get only an assert unless you set ".d { position: absolute; }". Trigger hang (separate issue, absolute not needed): 10px/10px/9999px 10px/10px/999999px --> "bad height" notreached */ /* Note: The -moz-column-gap and the backgrounds are just added here for easier visualization */ #colset { width: 200px; padding: 2px; -moz-column-count: 3; -moz-column-gap: 2px; } #a { height: 100px; background: lightblue;} #b { height: 50px; background: lightblue;} #c { height: 51px; background: orange;} div {page-break-inside:avoid; } </style> <script> function boom() { document.getElementById('colset').offsetHeight; document.getElementById('a').style.height = 'auto'; document.documentElement.className = '' } </script> </head> <!-- Removing whitespace in body for simpler frame trees --> <body onload="boom()" ><div id="colset" ><div ><div id="a"></div ><div id="b" ><div id="c"></div ><div id="d"></div ></div ></div ></div ></body> </html>