If you just want to use Host Access for the Cloud programatically in your web page without showing the web client, add headless: true to your ZFE constructor options.
<script src="https://zfe.company.com/webclient/connector/zfe-embed-sdk.js"></script>
<script>
var zfe = new ZFE.ZFE({
url: 'https://zfe.company.com/webclient/',
headless: true
});
zfe.connect().then(function () {
zfe.getSessionManager().getDescriptors();
});
</script>