<!DOCTYPE html>
<link rel="author" title="Mozilla" href="http://www.mozilla.org/">
<link rel="help" href="https://drafts.csswg.org/css-shapes-1/#supported-basic-shapes">
<link rel="help" href="https://bugzilla.mozilla.org/show_bug.cgi?id=1620671">

<style>
.a {
  float: left;
  min-height: 99vw;
  shape-outside: ellipse(61% 100% at 34% 62%);
}
</style>
<button class="a">
