url element and lang attribute

[van-de-bugger]

Is lang attribute allowed for url element?

For example if a project have localized homepage (or help page):

    <url type="homepage">http://example.org/en/home.html</url>
    <url type="homepage" lang="es">http://example.org/es/home.html</url>
    <url type="help">http://example.org/en/home.html</url>
    <url type="help" lang="es">http://example.org/es/home.html</url>

In such a case, appstreamcli 0.15.5 issues warnings:

W: example:74: url-redefined homepage
W: example:76: url-redefined help

Using xml:lang instead of plain lang does not help to avoid warnings. What is wrong with localized homapages, help, and other urls (donate, faq, bugtracker, etc)?

[ximion]

Is lang attribute allowed for url element?

No. If it were, the specification would mention it.
We expect websites to just auto-redirect to localized pages based on the web browser locale.