I have noticed this behavior consistently: the data table has a wrapper that extends beyond the table and blocks other controls outside the table (like some form controls in the screenshot). I've had to redact sensitive information, but you can see from the Chrome Developer tab and the visible part of the screenshot that the following div overlaps the select dropdown and form submit button:
<div id="DataTables_Table_0_wrapper" class="dataTables_wrapper form-inline dt-bootstrap no-footer">
How can I fix this so that the invisible wrapper doesn't block use of the form controls, as you see in the screenshot?