PUBLIC MARKS with tags firefox & validateur

This is a lint tool (like a non-authoritative validator) for XFN, rel-tag and other microformats that make use of the rel attribute of links. It takes the form of a bookmarklet you can add to your browser and then run against any page. rel-lint will check for known XFN values, flag values it doesn't recognise (even though they may well be correct) and display the tag values for rel-tagged links.

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HTML Validator is an Mozilla extension that adds HTML validation to Firefox and Mozilla. The number of errors of a HTML page is seen on the form of an icon in the status bar when browsing. The details of the errors are seen when looking the HTML source of the page.