Sets the rel canonical link tag to another hostname. Useful for SEO to prevent dup content penalty when content is identical to another URL with a different hostname. Be sure to edit the configuration and set the alternate hostname before enabling the plugin. For example, if the rel canonical url was http://foo.tld/blah and you set the alt host to bar.tld, the new rel canonical will be http://bar.tld/blah. There is also an option for using WP search query style. If enabled, the resulting rel canonical would be http://bar.tld/?s=blah