This may need to be fixed in 4.1 as well with the JSON microdata based on #30727

1. Pretty sure the changes here are not correct as they remove the special handling for the last item (might need more coffee before checking 100%)
2. with the JSON microdata it is valid to have the following. Note the item"" for the non-linked item

{
    "@context": "https://schema.org",
    "@type": "BreadcrumbList",
    "itemListElement": [
        {
            "@type": "ListItem",
            "position": 1,
            "name": "Home",
            "item": "https://www.example.com"
        },
        {
            "@type": "ListItem",
            "position": 2,
            "name": "Category",
            "item": ""
        },
        {
            "@type": "ListItem",
            "position": 3,
            "name": "item",
            "item": "https://www.example.com/category/page2"
        }
    ]
}

I did not remove the special handling for the last item. It's untouched.

Also, Google does not accept blank urls in 'item'; it marks it as invalid. I tested your code with the link above, this is what it Google says:

well that's annoying because https://validator.schema.org/ says its perfectly valid

I know, Google seems to be applying their own standard for structured data as it applies to rich search results.

FILE: /********/src/modules/mod_breadcrumbs/tmpl/default.php
----------------------------------------------------------------------
FOUND 3 ERRORS AFFECTING 3 LINES
----------------------------------------------------------------------
 51 | ERROR | [x] Whitespace found at end of line
    |       |     (Squiz.WhiteSpace.SuperfluousWhitespace.EndLine)
 58 | ERROR | [x] Whitespace found at end of line
    |       |     (Squiz.WhiteSpace.SuperfluousWhitespace.EndLine)
 60 | ERROR | [x] Whitespace found at end of line
    |       |     (Squiz.WhiteSpace.SuperfluousWhitespace.EndLine)

@crystalenka I've made review suggestions for the code style error which @brianteeman has mentioned in his previous comment. You can add them to a batch of suggestions and apply that with one click, or you can apply each of the suggestions separately with a direct click. I thought I do that to make it more comfortable for you.

@crystalenka I've made review suggestions for the code style error which @brianteeman has mentioned in his previous comment. You can add them to a batch of suggestions and apply that with one click, or you can apply each of the suggestions separately with a direct click. I thought I do that to make it more comfortable for you.

Thank you!!

@brianteeman Regarding the last item: It is not touched by this PR, and the if condition before that elseif is also not touched, so there should not be any change for that. If my understanding is right about how breadcrumbs and how menu items of type "Heading" or "Separator" work (which both are the types which have no link), it cannot happen that the last item of breadcrumbs belongs to a menu item of these types because to such menu items there is no navigation. So the PR should be ok as it is, no need to add the same logic changes for the last item. Or am I missing something?

I can confirm that before this PR google structure data test reports an error and after this pr it does not report an error.

I note however that the code for joomla 4.1 in the breadcrumbs is completely different

I guess this needs to be closed and remade for 4.1 - the code in 4.1 for the breadcrumbs structured data is completely different

Yeah, I will be taking a look at 4.1 to see if I can fix it there too but hadn't had a chance yet. I'll just close this one.