Nice, I wouldn't have thought that simple approach "download/overwrite" of self-modifying page served via file:/// protocol would be this viable and, after all, even intuitive.

For similar purpose (not-so-important semi-ephemeral notes and doodles) I usually (ab)use dataURI documents with "#hash" part and rely on browsers' history/bookmarks persistence, so both "editor engine" and "data" remains in URL and does not need to leave the browser.

Example: simple "HTML sandbox" with live preview under 1kb [1].

(Hypothetically they could be even synced to browser profiles, but. Also there presumably is a size limit for URI (or perhaps bookmarks database) but I haven't ran into it yet.)

Most probably not advisable for larger apps (even tiny feather wiki) but for it's super small purposes it has a nice advantage of "un-hosted" application/data can be passed around with clipboard. (Naturally, the "engine" works from a file as well [2], but the persistence remans in the "#hash" nevertheless.)

[1] https://gist.github.com/myfonj/c8ce74bf549e19600026ce9022388... [2] http://myfonj.github.io/sandbox.html