Mar 25 2019
Oct 12 2016
I've changed the title to reflect the intent for any kind of support for offline resources. Service workers would also be in the spirit of my original suggestion.
Oct 1 2016
In short, I think all three would be desirable to have as available options.
Although I think this change would be useful for many people, I think it may better to allow it as an (easily changeable) preference.