<table>
<tr>
<th>Column name</th>
<th>Column name</th>
</tr>
<tr>
<td>Column value</td>
<td>Column value</td>
<tr>
</table>
<table>
<tr>
<th>Column name</th>
<th>Column name</th>
</tr>
<tr>
<td>Column value</td>
<td>Column value</td>
<tr>
</table>
I'd like to process all tr that contain a td, but can only find contain queries for attributes and content; not elements. Is the latter possible with a single query?
Not directly, but you can use filter to get the appropriate rows
const rowsWithTd = [...document.querySelectorAll("table tr")].filter( x => x.querySelector("td"))
console.log(rowsWithTd.map(x => x.outerHTML))<table>
<tr>
<th>Column name</th>
</tr>
<tr>
<td>Column value</td>
<tr>
</table>
<table>
<tr>
<th>Column name</th>
</tr>
<tr>
<td>Column value</td>
<tr>
</table>