ANSWER:

If a file ends up in the application cache it will always be served from the application cache. Don’t put references to the manifest file in dynamic pages as they will then be added to the cache, the only way you will then be able to get the browser to load a new version of the page is to update the manifest file.

For more details on this and other gotchas have a read of Jake Archibald’s recent article Application Cache is a Douchebag.

by robertc from http://stackoverflow.com/questions/10739086