Trying to validate HTML on Joomla 2.5 site but I have some meta-problems

Question

I´m currently trying to clean up a Joomla 2.5 site for HTML validation but I have a problem.

The HTML validator is reporting the following errors:

Bad value og:title for attribute name on element meta: Keyword og:title is not registered.

Bad value og:type for attribute name on element meta: Keyword og:type is not registered

Bad value og:url for attribute name on element meta: Keyword og:url is not registered

Bad value og:site_name for attribute name on element meta: Keyword og:site_name is not registered

I have found out that the meta name attribute "og:xxxx" is generated only on pages that are linked to an article menu item. Unfortunately the front page is linked to such a menu item and I don´t know were the "og:" part is coming from.

I have tried to Google the problem and the only thing I can think is that it has do with Open Graph.

Reborn

I would check the plugins that are turned on for your site. I'm not sure that this is default Joomla behavior – Staircase

Yea, I have tried to locate any plugins or components that might cause this problem but I haven´t been able to find anything suspecious yet. I feel that I need to know what the "og:"-part of the name attribute means. – Reborn

I'm not very familiar with it, but it looks to be primarily Facebook specific. If you have a Facebook plugin of some kind, that is probably what is inserting the tag. At this point though, you would have to balance HTML5 validation with having Facebook on the site. I would typically lean towards Facebook over being specifically valid. – Staircase

Answer 1

og:title, og:type, og:url and og:site_name are values from the Open Graph protocol.

If they are not hardcoded in your theme, they are probably coming from a plugin (look for "Facebook", "Share" or "SEO" plugins).

However: Using these name values is not invalid! They are registered at MetaExtensions in the WHATWG wiki, which makes them valid according to the HTML5 spec. The validator is probably not up to date.

Phenylketonuria

Thanks for the explanation. I had a feeling it had to do with Open Graph. Nice to know that I don´t need to change this anyways. – Reborn