ed element roots
        // replace slots with slotted elements

        // Shadow-dom story:
        // Should be same except handling of slot replacement and element replacement
        // Just attach shadow instead

        // Stand-alone story
        // Upgrade elements, but don't wait for Alpine to hit "x-element" directive.
        // Just initialize element tree -->





















        <!--








            <div x-data="{ foo: 'baz' }">
                <the-outer class="bg-gray-100" :foo