modules/cms/client/img/svg/ui/editor/format-underline.svg
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<path d="M0 0h24v24H0z" fill="none"/>
<path d="M12 17c3.31 0 6-2.69 6-6V3h-2.5v8c0 1.93-1.57 3.5-3.5 3.5S8.5 12.93 8.5 11V3H6v8c0 3.31 2.69 6 6 6zm-7 2v2h14v-2H5z"/>
</svg>