In the case of a single celled tfoot the `:last-child` overrides the `:first-child` and leaves the table with a sharp bottom-left corner. An good example of this use case would be if you had a button action at the end of the table, similar to the first table example in the docs.
```
<table class="ui table segment">
<thead>
<tr><th>Name</th>
<th>Status</th>
<th>Notes</th>
</tr></thead>
<tbody>
<tr>
<td>John</td>
<td>Approved</td>
<td>None</td>
</tr>
<tr>
<td>Jamie</td>
<td>Approved</td>
<td>Requires call</td>
</tr>
<tr>
<td>Jill</td>
<td>Denied</td>
<td>None</td>
</tr>
</tbody>
<tfoot>
<tr><th colspan="3">
<div class="ui blue labeled icon button"><i class="user icon"></i> Add User</div>
</th>
</tr></tfoot>
</table>
<tfoot>
<tr><th></th></tr>
</tfoot>
</table>
```
There's probably a better way to do this, but it worked for me in my project.