As I said before, it's a 5-minute thing to get started with service-workers. Web-sites can use that and then you don't even need to save. There is this great offline library, fellow developers! Use it! What other platform gives you such easy-to-use offline capabilities?
> "not hijacking scrolling", "linkable URLs" and "not re-inventing <a href> badly"
You are dealing with a Turing-complete language here. Navigation situation is still way better than the applets.
What is the alternative you are supporting instead the current situation?