<!DOCTYPE html>
<html>
<head>
<link rel="author" href="mailto:sammy.gill@apple.com">
<link rel="help" href="https://drafts.csswg.org/css-box-4/#margin-trim-flex">
<meta name="assert" content="block-end trimmed margins should be reflected in computed style">
<style>
flexbox {
    display: flex;
    flex-direction: column;
    flex-wrap: wrap;
    width: 100px;
    height: 110px;
    margin-trim: block-end;
}
item {
    display: block;
    background-color: green;
    width: 50px;
    height: 50px;
    margin