Export to HTML of Tables structure is incorrect
InDesign CC2019+2020
Create a table
Convert first row to Header row type
Convert last row to Footer row type
Export to HTML
you get (simplified)
<table>
<thead>
<td>
<p>Text</p>
</td>
</thead>
<tfoot>
<td>
<p>Text</p>
</td>
</foot>
<tbody>
<td>
<p>Text</p>
</td>
</tbody>
The HTML spec specifies that tfoot should appear AFTER tbody.
Also the <td> in <thead> should be <th>.
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Shaun Curran commented
InDesign CC2019+2020
Create a table
Convert first row to Header row type
Convert last row to Footer row type
Export to HTMLyou get (simplified)
<table>
<thead>
<td>
<p>Text</p>
</td>
</thead>
<tfoot>
<td>
<p>Text</p>
</td>
</foot>
<tbody>
<td>
<p>Text</p>
</td>
</tbody>The HTML spec specifies that tfoot should appear AFTER tbody.
Also the <td> in <thead> should be <th>.