An important part of writing html is making sure that what you’ve written is valid code. W3C provides an excellent resource for validating. I will show you how to utilize this service to validate any page directly from a Firefox bookmark.

First, click on the ‘Bookmarks’ menu, and then right-click on ‘New Bookmark…’

Add text for the name that will be easy for you to remember. In the location text box paste the following javascript snippet:

javascript:void
(document.location='http://validator.w3.org/check?uri='+document.location+';verbose=1;ss=1')

Click the ‘Add’ button and test it out!