<div class="btn-toolbar w-100" role="toolbar" aria-label="Toolbar with button groups">

    <div class="btn-group mr-2 w-100" role="group" aria-label="First group">

        <button type="button" class="btn btn-default">1</button>

        <button type="button" class="btn btn-default">2</button>

    </div>

</div>

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