<!DOCTYPE html>
<style>
* {
margin-right:2vw;
}
body {
display:grid;
grid-auto-flow:row stack;
}
</style>
<script>
if (window.testRunner)
testRunner.dumpAsText();
</script>
<body>The test checks that embedded elements don't leave stale pointers into the grid representation.
<embed>This test has passed if it didn't crash.</embed>
</body>