The manifest cache API used in this plugin has been deprecated, and therefore so has this plugin.
Websites typically require an internet connection to work. Modern browsers do however include offline caching functionality via their cache manifest functionality. It is possible to set a website to cache itself inside the browser when loaded, so that if you need to revisit the page when it is offline, you may do so.
The Offline cache plugin for WordPress allows you to easily implement this functionality on your own website.
Requirements: PHP Dom module