Top add-on Rated 5 out of 5 stars

Such a great add-on, right up there with Firebug and Web developer extension as essential add-ons. The new OpenSP validator as used by the w3c validator is a fantastic new addition.

Certainly alot easier to use than installing the w3c validator on a windows dev machine. Keep up the great work.

This review is for a previous version of the add-on (