app/templates/components/icon-underline.hbs
<svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" class="feather feather-underline"><path d="M6 3v7a6 6 0 0 0 6 6 6 6 0 0 0 6-6V3"></path><line x1="4" y1="21" x2="20" y2="21"></line></svg>