[eyelidlessness]

I agree with other comments concerned with fingerprinting, and it was my second thought reading through the article. But my first thought was how beneficial this could be for return visitors of a web app, and how it could similarly benefit related concerns, such as managing local caches for offline service workers.

True, for documents (as is another comment’s focus) this is perhaps overkill. Although even there, a benefit could be imagined for a large body of documents—it’s unclear whether this case is addressed, but it certainly could be with appropriate support across say preload links[0]. But if “the web is for documents, not apps” isn’t the proverbial hill you’re prepared to die on, this is a very compelling story for web apps.

I don’t know if it’s so compelling that it outweighs privacy implications, but I expect the other browser engines will have some good insights on that.

0: https://developer.mozilla.org/en-US/docs/Web/HTML/Attributes...

[patrickmeenan]

Even in the "documents" case of the web there can be pretty significant savings if users tend to visit more than one page and they share some amount of structure.

On the first entry to the site you trigger the load of an external dictionary that contains the common parts of the HTML across the site and then future document loads can be delta-compressed against the dictionary, effectively delivering just the page-specific bits.

You need to amortize the cost of loading the dictionary across the other page loads but it's usually pretty compelling once users visit more than 2-3 pages.