<!DOCTYPE html>
<html>
<head>
<link rel="author" title="Myles C. Maxfield" href="mailto:mmaxfield@apple.com"/>
<link rel="help" href="https://drafts.csswg.org/css-fonts-4/#standard-font-families"/>
<link rel="mismatch" href="standard-font-family-18-notref.html"/>
<meta name="assert" content="ui-sans-serif's bold in @font-face isn't synthetic"/>
<style>
@font-face {
    font-family: "AppleSystemUISansSerif";
    src: local("ui-sans-serif");
}
</style>
</head>
<body>
<div>
<div style="display: inline-block; font: bold 72px 'AppleSystemUISansSerif'; font-synthesis: none;">HeJllo</div>
</div>
</body>
</html>