This add-on features action icons; when you visit a website, it detects the header and checks for the presence of the 'onion-location' parameter. If this parameter is present, the action icon becomes active and, when clicked, takes you to the onion version of the site found in the header; on onion sites, this icon disappears. This add-on cannot find the onion versions of websites unless they have been specified in the header itself.
