Let NVDA read aria-label of th

[venlahy]

Is your feature request related to a problem? Please describe.

I have a table like this:

<table>
    <thead>
        <tr>
            <th>First header</th>
            <th>
                Second header
                <button>Open additional info to second header</button>
            </th>
        </tr>
    </thead>
    <tbody>
        <tr>
            <td>Value 1</td>
            <td>Value 2</td>
        </tr>
    </tbody>
</table>

That table has an accessibility problem with the button. When I use a screen reader and step to the "Value 2" cell, I hear the screen reader saying also the text "Open additional info to second header" which I do not need to hear in the "Value 2" field. The screen reader says:
"Second header and Open additional info to second header Value 2, column 2 of 2".
but I would like the screen reader to say:
"Second header Value 2, column 2 of 2".

With VoiceOver, this problem can be fixed by adding an aria-label to the th. But to prevent VoiceOver from reading the "Second header" twice when stepping to the header cell, an aria-hidden attribute can be added. Like this:

<table>
    <thead>
        <tr>
            <th>First header</th>
            <th aria-label="Second header">
                <span aria-hidden="true">Second header</span>
                <button>Open additional info to second header</button>
            </th>
        </tr>
    </thead>
    <tbody>
        <tr>
            <td>Value 1</td>
            <td>Value 2</td>
        </tr>
    </tbody>
</table>

However, this solution does not work with NVDA, since NVDA does not read aria-labels of th elements. NVDA does not read the text "Second header" at all in the cell, so I cannot use this solution at all.

Describe the solution you'd like

I would expect NVDA to behave simirlarly to VoiceOver. I would expect NVDA to read the aria-labels of the table headers.

Describe alternatives you've considered

Additional context

[Adriani90]

cc: @SaschaCowley, @jcsteh maybe you have any thoughts on this as well, I think this approach might produce also redundant verbosity if aria label on th elements is misused in some circumstances. In this case the question is why should the user not get any information about the button?

[seanbudd]

This is intended behaviour, what part of the HTML/ARIA spec leads you to the reasoning for expected behaviour? Note VoiceOver might not be following the spec, or there could be multiple valid implementations within the spec.