Online
This page detects when the browser goes offline and stores data locally.
Use File > Work Offline in Firefox to switch online/offline modes.
Refresh the page in offline mode to reload data from store.
For more information, refer to the SitePoint article How To Create an Offline Web Application by Craig Buckler.
Please use the code as you wish at your own risk. It is provided as-is without warrranty of any kind.