I have tested this item ✅ successfully on 7bf3f2f

In my opinion, the role="navigation" attribute is unnecessary. You can leave it. But all popular browsers, including IE11, recognize the nav tag. Nav tag has role=navigation implicite entered. Leaving an attribute, however, will not be an error. In the W3C WAI tutorial, it is still recommended to place a redundant attribute of a role.
See: https://www.w3.org/WAI/tutorials/page-structure/regions/ :

Most current web browsers support the above HTML5 elements and convey the information to assistive technology through the accessibility APIs. However, to maximize compatibility with web browsers and assistive technologies that support WAI-ARIA but do not yet support HTML5, it is currently advisable to use both the HTML5 elements and the corresponding WAI-ARIA roles.

Personally, I am against entering a role attribute. But because we did this in other cases (e.g. in the pagination.php file), let it stay.

Sorry but you don't actually understand what the text you are quoting refers to.

The nav element is not exposed in the accessibility tree with internet explorer.

What you are seeing is that NVDA (and perhaps other screen readers have written a workaround to this IE bug) See nvaccess/nvda#6044

This only means that an NVDA and IE11 user is helped. It doesn't fix the bug in IE11 which we have no way of knowing if other assistive technology has their own work around.

So the correct conclusion is to have the role so that ALL users of assistive technology and IE 11 are covered.

We only support specific browsers. We do not support specific assistive technology

I am sorry. I don't know why you assume that I don't understand something. Maybe it' s you who don't understand something?
I wrote what my opinion is. I am free to have my opinion. At the same time I did a successful test.
Please see the new W3C WAI page.
https://www.w3.org/WAI/
Please check in the code that the new HTML5 tags (header, nav, main, footer, etc) are used without the role=" attribute.
Of course, you can say that W3C WAI does wrong. For me this is the correct pattern.
Using these tags (which have an implicitly entered role) without role attributes is correct (and not, as you say, incorrect). Even if some technologies do not support these tags yet.

Sorry I can't help it if you don't understand the difference between the html 5 specification and the browsers implementation of it and it's the accessibility html5 mapping specification aka html-aam

@brianteeman believe me, I understand.

This PR adds a feature and may break existing templates without overrides, so this will likely not go into J3.

There is already a J4 PR for this #23685 correct.

@HLeithner
For 3.x if it. Is changed to div role=navigation it will not break anything and it will be more accessible than it was before

This PR adds a NAV-tag around the UL-tag and this can break templates.

Yes which is why I wrote what I wrote

Maybe break less but why can't it be added to the UL?

it can be but it would be invalid html

1. How will adding nav tag damage existing templates? The Breadcrumb is stylized with the breadcrumb class. Of course, it is always possible that some inexperienced webmaster will use some special formatting for the 'nav' tag. But we won't be able to do that.
2. Adding an attribute role="navigation" to div tag is not an error if you cannot use nav tag (for ex. in HTML4 document), but adding to ul tag is the error! But there is no justification here that excludes the use of nav tag.
3. Let me also remind you:

6.1.7 Rendered markup
For the time being, rendered markup is not subject to our backwards compatibility promise. We will try not to change markup in such a way that a site might render differently, but we can't promise not to break anything at the present time. We will work on defining ways in which we might make a backwards compatibility promise for markup in the future, but we do not currently have a satisfactory consensus on a workable standard.
https://developer.joomla.org/development-strategy.html

I have tested this item ✅ successfully on f57389c

I have tested this item ? unsuccessfully on f57389c

You cant close a div with a nav :(

@zwiastunsw how did you successfully test - the markup is wrong

Yes, my mistake.

I have tested this item ✅ successfully on ede34b4

now is OK

I have tested this item ✅ successfully on ede34b4

Thats better - thanks

I have tested this item ✅ successfully on ede34b4

Thats better - thanks

RTC

@HLeithner Please merge this PR, nav was changed to div as requested.

I requested a different change that seams not to be vaild, thats the reason I didn't merged it.

@HLeithner This PR now adapt changes suggested ny @brianteeman in #23691 (comment) see https://github.com/joomla/joomla-cms/pull/23691/files?utf8=%E2%9C%93&diff=unified&w=1

I merge it anyway, thx