newsupernova/vendor/magento/module-security/view/adminhtml/page_layout/admin-popup.xml

<?xml version="1.0"?>
<!--
/**
 * Copyright © Magento, Inc. All rights reserved.
 * See COPYING.txt for license details.
 */
-->
<layout xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:View/Layout/etc/page_layout.xsd">
    <container name="backend.session.activity">
        <container name="after.body.start" as="after.body.start" label="Page Top" before="-"/>
        <container name="page.wrapper" as="page_wrapper" htmlTag="div" htmlClass="page-wrapper">
            <container name="page.main.container" as="page_main_container" htmlId="page:main-container" htmlTag="div" htmlClass="page-columns">
                <container name="main.col" as="main-col" htmlId="container" htmlTag="div" htmlClass="main-col">
                    <container name="content" as="content" />
                </container>
            </container>
            <container name="js" as="js" label="JavaScript"/>
        </container>
        <container name="before.body.end" as="before_body_end" label="Before Body End" after="-"/>
    </container>
</layout>