A plugin with common features missed in WordPress, like favicon, meta tags,
adding HTML to head and footer, WordPress e-mail from header filter, etc.
This widget will submit your wordpress RSS feed to feedvalidator.org, and check the results to verify your feed is valid.
CiteKite automatically validates quotations you make of other websites and lets the world know you care.
This plugin shows the xhtml and css validity of an entry, in the entry.
This is a simple plugin for WordPress to test if the visitors ISP supports DNSSEC. The result is displayd in a widget.
This plugin performs a batch markup validation check over your entire WordPress website.
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