<!DOCTYPE html>
<html id="a">
<link rel="help" href="https://bugzilla.mozilla.org/show_bug.cgi?id=1674011">

<style>
:not(animateTransform) { columns: 1px }
</style>
<script>
function go() {
  a.appendChild(b)
}
function eh() {
  a.appendChild(c)
}
</script>
<body onload=go()>
<data id="b">x</command>
<dir style="column-span: all">x</dir>
<details id="c" ontoggle="eh()" open="">x</details>
<iframe align="right">x</iframe>
